AJ7UU - Amateur Station

Arduino Morse Code Sketch

2022-12-26T16:18:00.008-07:00

An Arduino sketch that takes text input and flashes the internal LED and buzzes a buzzer in Morse code.

The digital output on pin 12 could operate a relay that could be connected to a radio Key input so it could send Morse code over the air.

/*
Morse Code Sketch - Copyright Timothy Millea 2022 - Released under Creative Commons Attribution 4.0 International License

Takes a String variable and flashes on board led and buzzes passive speaker in morse code

INSTRUCTIONS
1. Open Serial Monitor console
2. Make sure New Line is selected a line termination
3. Enter sentence to convert to morse code
4. Press the enter key

*/

//define variables
int morseLED = 13;  //onboard LED
int morseSND = 12;  //pin for speaker
int WPM = 25;       //default 13 words per minute
int multiplier = 1200 / WPM;
int delayInterSpace = 1 * multiplier;
int delayDIT = 1 * multiplier;
int delayDAH = 3 * multiplier;
int delayCharSpacing = 3 * multiplier;
int delayWordSpacing = 7 * multiplier;
bool stringComplete = false;
String inputString;  // a string to hold incoming data

void setup() {
  // put your setup code here, to run once:
  pinMode(morseSND, OUTPUT);  //speaker goes on this pin
  pinMode(morseLED, OUTPUT);  //onboard LED
  Serial.begin(9600);

  Serial.println();
  Serial.println();
  Serial.println("~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~");
  Serial.println("                   MorseUNO");
  Serial.println("~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~");
  Serial.println("~ Command mode");
  Serial.println("Current commands:");
  Serial.println("~WPM - lists current or sets new WPM speed (~WPM or ~WPM 25)");
  Serial.println("~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~");
  Serial.print("Current WPM: ");
  Serial.println(WPM);
  flashSentence("MorseUNO");
  Serial.println();
  Serial.println("Ready!");
}

void loop() {
  // put your main code here, to run repeatedly:
  if (stringComplete) {
    Serial.println("");
    Serial.println(inputString);
    if (inputString.startsWith("~")) {
      //this is a command
      inputString.toUpperCase();
      inputString.remove(0, 1);
      if (inputString.startsWith("WPM")) {
        inputString.remove(0, 4);
        inputString.trim();
        if (inputString.toInt() == 0) {
          Serial.print("Current WPM: ");
          Serial.println(WPM);
          return;
        }
        WPM = inputString.toInt();
        Serial.print("Set WPM to: ");
        Serial.println(WPM);
        multiplier = 1200 / WPM;
        delayInterSpace = 1 * multiplier;
        delayDIT = 1 * multiplier;
        delayDAH = 3 * multiplier;
        delayCharSpacing = 3 * multiplier;
        delayWordSpacing = 7 * multiplier;
      }
    } else {
      flashSentence(inputString);
      Serial.println("");
    }
    inputString = "";
    stringComplete = false;
  }  //if read serial console complete
}  //loop()

void flashLetter(char letter) {
  //this isn't elegant but it gets the job done
  Serial.print(letter);
  if (letter == 'A') {
    flashDIT();
    flashDAH();
  } else if (letter == 'B') {
    flashDAH();
    flashDIT();
    flashDIT();
    flashDIT();
  } else if (letter == 'C') {
    flashDAH();
    flashDIT();
    flashDAH();
    flashDIT();
  } else if (letter == 'D') {
    flashDAH();
    flashDIT();
    flashDIT();
  } else if (letter == 'E') {
    flashDIT();
  } else if (letter == 'F') {
    flashDIT();
    flashDIT();
    flashDAH();
    flashDIT();
  } else if (letter == 'G') {
    flashDAH();
    flashDAH();
    flashDIT();
  } else if (letter == 'H') {
    flashDIT();
    flashDIT();
    flashDIT();
    flashDIT();
  } else if (letter == 'I') {
    flashDIT();
    flashDIT();
  } else if (letter == 'J') {
    flashDIT();
    flashDAH();
    flashDAH();
    flashDAH();
  } else if (letter == 'K') {
    flashDAH();
    flashDIT();
    flashDAH();
  } else if (letter == 'L') {
    flashDIT();
    flashDAH();
    flashDIT();
    flashDIT();
  } else if (letter == 'M') {
    flashDAH();
    flashDAH();
  } else if (letter == 'N') {
    flashDAH();
    flashDIT();
  } else if (letter == 'O') {
    flashDAH();
    flashDAH();
    flashDAH();
  } else if (letter == 'P') {
    flashDIT();
    flashDAH();
    flashDAH();
    flashDIT();
  } else if (letter == 'Q') {
    flashDAH();
    flashDAH();
    flashDIT();
    flashDAH();
  } else if (letter == 'R') {
    flashDIT();
    flashDAH();
    flashDIT();
  } else if (letter == 'S') {
    flashDIT();
    flashDIT();
    flashDIT();
  } else if (letter == 'T') {
    flashDAH();
  } else if (letter == 'U') {
    flashDIT();
    flashDIT();
    flashDAH();
  } else if (letter == 'V') {
    flashDIT();
    flashDIT();
    flashDIT();
    flashDAH();
  } else if (letter == 'W') {
    flashDIT();
    flashDAH();
    flashDAH();
  } else if (letter == 'X') {
    flashDAH();
    flashDIT();
    flashDIT();
    flashDAH();
  } else if (letter == 'Y') {
    flashDAH();
    flashDIT();
    flashDAH();
    flashDAH();
  } else if (letter == 'Z') {
    flashDAH();
    flashDAH();
    flashDIT();
    flashDIT();
  }
  //numeral characters
  else if (letter == '0') {
    flashDAH();
    flashDAH();
    flashDAH();
    flashDAH();
    flashDAH();
  } else if (letter == '1') {
    flashDIT();
    flashDAH();
    flashDAH();
    flashDAH();
    flashDAH();
  } else if (letter == '2') {
    flashDIT();
    flashDIT();
    flashDAH();
    flashDAH();
    flashDAH();
  } else if (letter == '3') {
    flashDIT();
    flashDIT();
    flashDIT();
    flashDAH();
    flashDAH();
  } else if (letter == '4') {
    flashDIT();
    flashDIT();
    flashDIT();
    flashDIT();
    flashDAH();
  } else if (letter == '5') {
    flashDIT();
    flashDIT();
    flashDIT();
    flashDIT();
    flashDIT();
  } else if (letter == '6') {
    flashDAH();
    flashDIT();
    flashDIT();
    flashDIT();
    flashDIT();
  } else if (letter == '7') {
    flashDAH();
    flashDAH();
    flashDIT();
    flashDIT();
    flashDIT();
  } else if (letter == '8') {
    flashDAH();
    flashDAH();
    flashDAH();
    flashDIT();
    flashDIT();
  } else if (letter == '9') {
    flashDAH();
    flashDAH();
    flashDAH();
    flashDAH();
    flashDIT();
  }
  //punctuation characters
  else if (letter == '$') {
    flashDIT();
    flashDIT();
    flashDIT();
    flashDAH();
    flashDIT();
    flashDIT();
    flashDAH();
  } else if (letter == '+') {
    flashDIT();
    flashDAH();
    flashDIT();
    flashDAH();
    flashDIT();
  } else if (letter == ',') {
    flashDAH();
    flashDAH();
    flashDIT();
    flashDIT();
    flashDAH();
    flashDAH();
  } else if (letter == '-') {
    flashDAH();
    flashDIT();
    flashDIT();
    flashDIT();
    flashDIT();
    flashDAH();
  } else if (letter == '.') {
    flashDIT();
    flashDAH();
    flashDIT();
    flashDAH();
    flashDIT();
    flashDAH();
  } else if (letter == '/') {
    flashDAH();
    flashDIT();
    flashDIT();
    flashDAH();
    flashDIT();
  } else if (letter == ':') {
    flashDAH();
    flashDAH();
    flashDAH();
    flashDIT();
    flashDIT();
    flashDIT();
  } else if (letter == ';') {
    flashDAH();
    flashDIT();
    flashDAH();
    flashDIT();
    flashDAH();
    flashDIT();
  } else if (letter == '=') {
    flashDAH();
    flashDIT();
    flashDIT();
    flashDIT();
    flashDAH();
  } else if (letter == '?') {
    flashDIT();
    flashDIT();
    flashDAH();
    flashDAH();
    flashDIT();
    flashDIT();
  } else if (letter == '@') {
    flashDIT();
    flashDAH();
    flashDAH();
    flashDIT();
    flashDAH();
    flashDIT();
  } else if (letter == '!') {
    flashDAH();
    flashDAH();
    flashDAH();
    flashDIT();
  }


}  //flashLetter()

void flashWord(String word) {
  //break word into chars
  for (int i = 0; i < word.length(); i++) {
    flashLetter(word.charAt(i));
    delay(delayWordSpacing - delayCharSpacing);
  }  //for each character in word
}  //flashWord()

void flashSentence(String text) {
  int splitCount = countSplitCharacters(text, ' ');
  String wordArray[splitCount + 1];
  int index1 = 0;
  int index2 = 0;
  for (int i = 0; i < splitCount + 1; i++) {
    //find the start and end index of the words by finding the space character
    if (index1 > 0) {
      index1 = text.indexOf(' ', index2);
    }
    index2 = text.indexOf(' ', index1 + 1);
    if (index2 < 0) {
      index2 = text.length();
    }
    //parse the word from the string
    String word = text.substring(index1++, index2);
    word.toUpperCase();   //convert to uppercase
    wordArray[i] = word;  //add word to array
  }                       //for each word in sentance
  for (int i = 0; i < splitCount + 1; i++) {
    flashWord(wordArray[i]);
  }  //for each word in array
  delay(delayWordSpacing);
}  //flashSentence()

void serialEvent() {
  while (Serial.available()) {
    char inChar = (char)Serial.read();
    if (inChar == '\n') {
      stringComplete = true;
    }  //if we have a newline then we're done reading serial for now
    if (stringComplete == false) {
      inputString += inChar;
    }  //if no newline then append the char to the string
  }    //while stuff ready to read from serial console
}  //serialEvent()

int countSplitCharacters(String text, char splitChar) {
  int returnValue = 0;
  int index = 0;
  while (index > -1) {
    index = text.indexOf(splitChar, index + 1);
    if (index > -1) returnValue++;
  }
  return returnValue;
}  //countSplitCharacters

void flashDIT() {
  digitalWrite(morseSND, HIGH);
  digitalWrite(morseLED, HIGH);
  delay(delayDIT);
  digitalWrite(morseSND, LOW);
  digitalWrite(morseLED, LOW);
  delay(delayInterSpace);
}  //flashDIT()

void flashDAH() {
  digitalWrite(morseSND, HIGH);
  digitalWrite(morseLED, HIGH);
  delay(delayDAH);
  digitalWrite(morseSND, LOW);
  digitalWrite(morseLED, LOW);
  delay(delayInterSpace);
}  //flashDAH()

My BBB Projects Blog

2014-07-18T09:32:00.004-07:00

A link to my blog tracking my Beaglebone Black projects.

http://mybbbprojects.blogspot.com/

Passing AES keys through RSA public key encryption (PERL)

2014-06-29T15:28:00.000-07:00

I've been interested with encryption for a while but never found a reason to actually write any code about it until recently.

Here is a sample perl script that goes through the motions of passing AES 256 key through an RSA public key encryption and then goes on to decrypt a message encrypted with the AES key.

The encrypted AES key and the encrypted message are both encoded in base64 for passing through email or other ASCII method of transfer.

I wrote this script as a learning tool to understand the AES and RSA methods. Other than that this script has no usefulness.

You may use this script in whole or part to further your understanding of cryptography methods.

I make no claims that this is the best way to accomplish passing a key to someone but it is a method. I also make no claims that this code is correct and welcome any comments/suggestions to improve the process, especially the generation of the AES key. I have no idea if the method I use is considered secure.

############################################################################
#!/usr/local/bin/perl

use strict;
use warnings;

use Crypt::CBC;
use MIME::Base64;
use Crypt::OpenSSL::RSA;
use Digest::SHA qw(sha1 sha1_hex sha1_base64 sha384 sha512 sha512_hex sha512_base64 sha256 sha256_hex sha256_base64 hmac_sha256 hmac_sha256_base64 hmac_sha256_hex hmac_sha512 hmac_sha512_base64);
use Bytes::Random::Secure qw(
        random_bytes random_bytes_base64 random_bytes_hex
    );

##############################################################################
#Generate the keys
##############################################################################
print "#######################################################################
# Generate the keys
#######################################################################\n\n";

my (%rsa_key_pair); #using a hash to store my private/public and other public keys. The hash itself is not encrypted but that is trivial to fix once we learn how to do it with AES

#also since this is a tutorial we generate a new set of keys each time the script is run - in the real world we'd need to dig these keys out of a key file stored on a drive
#this key file should also be encrypted with a passphrase (not discussed in this tutorial)

print "Generating RSA key pair...\n\n";

        my $rsa = Crypt::OpenSSL::RSA->generate_key(2048);

        my $keyidx = $rsa->get_public_key_string() if defined $rsa; #get the index of the key-pair

        $keyidx = sha512_hex( $keyidx, "" ); #hash the index
        $keyidx = substr( $keyidx, 0, 6 ); #shorten the hash to 6 digits

        $rsa_key_pair{$keyidx}{'pubK'} = $rsa->get_public_key_string(); #load the hash
        $rsa_key_pair{$keyidx}{'privK'} = $rsa->get_private_key_string();
        $rsa_key_pair{$keyidx}{'Local'} = 1;

my $rsa_public_key = $rsa_key_pair{$keyidx}{'pubK'}; #set local key variables - not necessary but convenient
my $rsa_private_key = $rsa_key_pair{$keyidx}{'privK'};

#print $rsa_private_key; #print them if you want to see them
#print "\n\n";
#print $rsa_public_key;
#print "\n\n";

print "Generating AES key...\n\n";

my $random_generator = Bytes::Random::Secure->new(
    Bits        => 64,
    NonBlocking => 1,
); # Seed with 64 bits, and use /dev/urandom (or other non-blocking).

my $AES32byte_random = $random_generator->bytes(32); # A string of 32 random bytes which we'll use as the AES key

print "AES32byte_random: ";
print $AES32byte_random;
print "\nSizeof AES32byte_random: ";
print length $AES32byte_random;
print "\n\n";

##############################################################################
#The encryption process
##############################################################################
print "#######################################################################
# The Encryption Process
#######################################################################\n\n";
my $RSA_en_cipher = Crypt::OpenSSL::RSA->new_public_key($rsa_public_key); #create a new public key cipher object

my $binary_encrypted_key = $RSA_en_cipher->encrypt($AES32byte_random); # encrypt the AES key

print "Binary encrypted key: \n";
print $binary_encrypted_key;
print "\n\n";

my $encoded_encrypted_key = encode_base64($binary_encrypted_key); #encode the encrypted AES key - encrypt and encode can be combined in one line - this is a tutorial

print "Encoded encrypted key: \n" . $encoded_encrypted_key . "\n\n";
#at this point send the encoded encrypted key to the private key holder via email or text message etc.

#the message to encrypt - why we're doing this exercise - well one of the reasons anyway
my $cleartext = "This module is a Perl-only implementation of the cryptographic cipher block chaining mode (CBC).
In combination with a block cipher such as DES or IDEA, you can encrypt and decrypt messages of arbitrarily long length.
The encrypted messages are compatible with the encryption format used by the OpenSSL package.

To use this module, you will first create a Crypt::CBC cipher object with new().
At the time of cipher creation, you specify an encryption key to use and, optionally, a block encryption algorithm.
You will then call the start() method to initialize the encryption or decryption process,
crypt() to encrypt or decrypt one or more blocks of data, and lastly finish(), to pad and encrypt the final block.
For your convenience, you can call the encrypt() and decrypt() methods to operate on a whole data value at once.";

#create the AES encryption cipher object
my $AES_en_cryption_cipher = Crypt::CBC->new(
        {
                'key'           => $AES32byte_random,
                'cipher'        => 'Rijndael',
                'padding'       => 'standard',

        });


my $AES_en_crypted_message = $AES_en_cryption_cipher->encrypt($cleartext); #encrypt the message

print "Encrypted message:\n";
print $AES_en_crypted_message;
print "\n\n";

my $encoded_AES_en_crypted_message = encode_base64($AES_en_crypted_message); #encode the encrypted message to send via email etc.

print "Encoded encrypted message:\n";
print $encoded_AES_en_crypted_message;
print "\n\n";

#Now pass the message via email etc. to the other person who should now have the AES key decrypted so they can now decrypt the message

##############################################################################
#The decryption process - this happens at the private keyholder's side - this is a tutorial
##############################################################################
print "#######################################################################
# The Decryption Process
#######################################################################\n\n";

#decode
print "Decoding keys...\n";

my $encoded_decryption_key = $encoded_encrypted_key; #just to keep the variables separate - this also simulates the passing of the encrypted key via email etc.

print "Encoded decryption key: \n" . $encoded_decryption_key . "\n\n";

my $binary_decryption_key = decode_base64($encoded_decryption_key); #decode the key into binary so we can decrypt it

print "Binary decryption key: \n" . $binary_decryption_key . "\n\n";

#decrypt
print "Decrypting keys...\n";

my $RSA_de_cipher = Crypt::OpenSSL::RSA->new_private_key($rsa_private_key); # create a new decryption cipher object using the PRIVATE key

my $binary_decrypted_key = $RSA_de_cipher->decrypt($binary_decryption_key); # decrypt the AES key

print "Binary decrypted key: \n" . $binary_decrypted_key . "\n\n\n"; #this should be the binary 256bit binary AES key

#let's test that
print "Testing AES key pass through RSA public key encryption:\n\n";
print $AES32byte_random . "\n\n - should equal - \n\n" . $binary_decrypted_key . "\n\n"; #print the two binary keys - do they line up? - visual compare

if ($AES32byte_random eq $binary_decrypted_key) #let the computer compare then too
{
        print "\nSUCCESS!\n\n";
}
        else
        {
        print "\nFAIL! Now exiting!\n\n";
        exit;
}
print "Now to decrypt the message with the passed AES key...\n\n";

#create a new AES encryption cipher object
my $AES_de_cryption_cipher = Crypt::CBC->new(
        {
                'key'           => $binary_decrypted_key, #uses the binary AES key we just decoded and decrypted
                'cipher'        => 'Rijndael', #aka AES
                'padding'       => 'standard', #padding is a good thing so we can use this key more than once

        });

my $message_to_decode = $encoded_AES_en_crypted_message; #here is the simulated encrypted message send through email etc.

print "Encoded message to decrypt:\n";
print $message_to_decode;
print "\n\n";

$message_to_decode = decode_base64($message_to_decode); #decode into binary

print "Decoded message to decrypt:\n";
print $message_to_decode;
print "\n\n";

my $decoded_message = $AES_de_cryption_cipher->decrypt($message_to_decode); #decode the message

print "Decrypted message:\n"; #should be the same as the $cleartext variable above
print $decoded_message;
print "\n\n";

#let's test it
print "Testing if decode was successful...\n";

if ($decoded_message eq $cleartext)
{
        print "\nMessages match - SUCCESS!\n\n";
}
        else
        {
        print "\nMessages do NOT match - FAIL! Now exiting!\n\n";
        exit;
}

exit;
###################################################################
#script run output
###################################################################
#######################################################################
# Generate the keys
#######################################################################

Generating RSA key pair...

Generating AES key...

AES32byte_random: g&ÿ}■·ºQ♂╚rF░%Y¡▀}╨;┐█¶Ñ3~Ç≡╞ª►▒
Sizeof AES32byte_random: 32

#######################################################################
# The Encryption Process
#######################################################################

Binary encrypted key:
←╖Ä     ▼╣è♥à☻;XÉzMIè√0H0Ω↨í░ônö╔≈z▓|1§⌐╚£*∙V☼ªE≡9╧'N┬N/àb╨Xjgzƒ█l4▲{═☻√■W╬p☺╢7ê
x.╪K
z5♦!Éèê¡*ä■⌠╥B╨CGPoΘ╝îσxδ╬╜;>9q]‼ε/Vτúf7îª╢ö╞Ü9┤&A«O╓
âh#╛F░-å♠▒╬╣♂∞╙┴≥`£╣≡■ó╤
BΓû║áy\ìÅ░3╢╢@à╟AF╨▄Σ╕╞;╜⌂2/ëδ§"Hîw┤║↔![╠↨3Æ>↔]cQå«{¿╦¼↕à╜┬←ôMfñ╥╕╬ú.æB∞Σ<û

Encoded encrypted key:
G7eOCR+5igOFAjtYkHpNSYr7MEgw6hehsJNulMn3erJ8MRWpyJwq+VYPpkXwOc8nTsJOL4Vi0Fhq
Z3qf22w0HnvNAvv+V85wAbY3iHgu2EsKejUEIZCKiK0qhP700kLQQ0dQb+m8jOV46869Oz45cV0T
7i9W56NmN4ymtpTGmjm0JkGuT9YKg2gjvkawLYYHBrHOuQvs08HyYJy58P6i0QokOP/ysLmx35d7
9PWhkz0vKig1DULilrqgeVyNj7AztrZAhcdBRtDc5LjGO71/Mi+J6xUiSIx3tLodIVvMFzOSPh1d
Y1GGrnuoy6wShb3CG5NNZqTSuM6jLpFC7OQ8lg==

Encrypted message:
σgò↨ⁿ¼╖báv+▒É▼¡êΦáª#gJ¼èo[ÖiV▲ª╘kÖ7v»wQa╩0g-Σ└ÖfVÖ♫╢æù8àΣ§gìºφ=æBΦCJ│äÆw■σB0¥ 2╔
æm╫>Cí▐▼Äc!3☻æY(ß╥¡ΦEôéM┌á─o?íτt▄┌█¿§Σtφ{▓¥«ε╕p☺↓Ç=3╥61≡D╡√ÜW⌡αow╒╝√Q⌡ò⌐╘(↓‼Xw♠Ä
┴Ö☻ª{ë╔Z▓ε♀]o4Éc+♥_¡α(▬"ºH♂ë\&K┌d$☺/z☼▲╙☻¼┤à)Γ╒>,▀\█♂NÅ:,└┐∙φ&L☼!7☺;m╚¬h≈┴à▼+♥│d
oYGR∙U;hÆKK╖¶Γ░♥@;çî╗E▀▒l≥╢P←é☺úIÜjg┬B▒~╧(δä5@á¬½°╛L♫`τge‼íK%}¬fµé'     k▀ä▌∙⌐S▒
)j╨╫♂2uäü⌂ºb↨8⌡≤x╨0▒"┬♦▌ñ»♫↓╛PÖ╦;nΘ,Éû▒å,8╔â↕╡'<»≡:╜╫c╫Ü▒Φ·LΓô;µ¬☻░G■±èJδT☼╘{█É↨
xg▲zôVQ♠▼↨├)►c╢$²╓τzùvßπX♣^╜YkPà↑Θ{j¶╚½½`î0«Æ╓⌐Ä│↑.ì▬₧▌►S♥└►Ü[¿x┐6N]i╘UµtF↕_S▄↔Ä
↑¿²├L}y*┤╠═Ä╝÷┘╣1╨# üB{¬°S┌☻*'≤ñúä▌]ö§Üε,üª╬ú6▬Vu'¶Σ0╡k!╛ûúÖE*_%☺╗ö╟▄bε╜²╤{V¼╨╗√f├╖╡I▼┼≤≤∟[Θⁿ7n┤≥Ñ╠╗♫ÑÇ┬8
♦☼·Hæ▓☺#ΣìY>[µ╗`

Encoded encrypted message: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=

#######################################################################
# The Decryption Process
#######################################################################

Decoding keys...
Encoded decryption key:
G7eOCR+5igOFAjtYkHpNSYr7MEgw6hehsJNulMn3erJ8MRWpyJwq+VYPpkXwOc8nTsJOL4Vi0Fhq
Z3qf22w0HnvNAvv+V85wAbY3iHgu2EsKejUEIZCKiK0qhP700kLQQ0dQb+m8jOV46869Oz45cV0T
7i9W56NmN4ymtpTGmjm0JkGuT9YKg2gjvkawLYYHBrHOuQvs08HyYJy58P6i0QokOP/ysLmx35d7
9PWhkz0vKig1DULilrqgeVyNj7AztrZAhcdBRtDc5LjGO71/Mi+J6xUiSIx3tLodIVvMFzOSPh1d
Y1GGrnuoy6wShb3CG5NNZqTSuM6jLpFC7OQ8lg==

Binary decryption key:
←╖Ä     ▼╣è♥à☻;XÉzMIè√0H0Ω↨í░ônö╔≈z▓|1§⌐╚£*∙V☼ªE≡9╧'N┬N/àb╨Xjgzƒ█l4▲{═☻√■W╬p☺╢7ê
x.╪K
z5♦!Éèê¡*ä■⌠╥B╨CGPoΘ╝îσxδ╬╜;>9q]‼ε/Vτúf7îª╢ö╞Ü9┤&A«O╓
âh#╛F░-å♠▒╬╣♂∞╙┴≥`£╣≡■ó╤
BΓû║áy\ìÅ░3╢╢@à╟AF╨▄Σ╕╞;╜⌂2/ëδ§"Hîw┤║↔![╠↨3Æ>↔]cQå«{¿╦¼↕à╜┬←ôMfñ╥╕╬ú.æB∞Σ<û

Decrypting keys...
Binary decrypted key:
g&ÿ}■·ºQ♂╚rF░%Y¡▀}╨;┐█¶Ñ3~Ç≡╞ª►▒

Testing AES key pass through RSA public key encryption:

g&ÿ}■·ºQ♂╚rF░%Y¡▀}╨;┐█¶Ñ3~Ç≡╞ª►▒

- should equal -

g&ÿ}■·ºQ♂╚rF░%Y¡▀}╨;┐█¶Ñ3~Ç≡╞ª►▒

SUCCESS!

Now to decrypt the message with the passed AES key...

Encoded message to decrypt: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=

Decoded message to decrypt:
σgò↨ⁿ¼╖báv+▒É▼¡êΦáª#gJ¼èo[ÖiV▲ª╘kÖ7v»wQa╩0g-Σ└ÖfVÖ♫╢æù8àΣ§gìºφ=æBΦCJ│äÆw■σB0¥ 2╔
æm╫>Cí▐▼Äc!3☻æY(ß╥¡ΦEôéM┌á─o?íτt▄┌█¿§Σtφ{▓¥«ε╕p☺↓Ç=3╥61≡D╡√ÜW⌡αow╒╝√Q⌡ò⌐╘(↓‼Xw♠Ä
┴Ö☻ª{ë╔Z▓ε♀]o4Éc+♥_¡α(▬"ºH♂ë\&K┌d$☺/z☼▲╙☻¼┤à)Γ╒>,▀\█♂NÅ:,└┐∙φ&L☼!7☺;m╚¬h≈┴à▼+♥│d
oYGR∙U;hÆKK╖¶Γ░♥@;çî╗E▀▒l≥╢P←é☺úIÜjg┬B▒~╧(δä5@á¬½°╛L♫`τge‼íK%}¬fµé'     k▀ä▌∙⌐S▒
)j╨╫♂2uäü⌂ºb↨8⌡≤x╨0▒"┬♦▌ñ»♫↓╛PÖ╦;nΘ,Éû▒å,8╔â↕╡'<»≡:╜╫c╫Ü▒Φ·LΓô;µ¬☻░G■±èJδT☼╘{█É↨
xg▲zôVQ♠▼↨├)►c╢$²╓τzùvßπX♣^╜YkPà↑Θ{j¶╚½½`î0«Æ╓⌐Ä│↑.ì▬₧▌►S♥└►Ü[¿x┐6N]i╘UµtF↕_S▄↔Ä
↑¿²├L}y*┤╠═Ä╝÷┘╣1╨# üB{¬°S┌☻*'≤ñúä▌]ö§Üε,üª╬ú6▬Vu'¶Σ0╡k!╛ûúÖE*_%☺╗ö╟▄bε╜²╤{V¼╨╗√f├╖╡I▼┼≤≤∟[Θⁿ7n┤≥Ñ╠╗♫ÑÇ┬8
♦☼·Hæ▓☺#ΣìY>[µ╗`

Decoded message:
This module is a Perl-only implementation of the cryptographic cipher block chai
ning mode (CBC).
In combination with a block cipher such as DES or IDEA, you can encrypt and decr
ypt messages of arbitrarily long length.
The encrypted messages are compatible with the encryption format used by the Ope
nSSL package.

To use this module, you will first create a Crypt::CBC cipher object with new().

At the time of cipher creation, you specify an encryption key to use and, option
ally, a block encryption algorithm.
You will then call the start() method to initialize the encryption or decryption
process,
crypt() to encrypt or decrypt one or more blocks of data, and lastly finish(), t
o pad and encrypt the final block.
For your convenience, you can call the encrypt() and decrypt() methods to operat
e on a whole data value at once.

Testing if decode was successful...

Messages match - SUCCESS!

Press any key to continue . . .

924 QSOs on my 897D

2014-03-30T18:58:00.002-07:00

It's been just over a year and I decided to inquire as to how many QSOs I've had on it.

In exactly 365 days since I first used it I've had 924 QSOs.

Running total so far is 956 QSOs, mostly digital and more specifically JT65HF.

Still missing 4 states and like 60 some-odd countries confirmed for WAS and DXCC.

Some day I'll pop the log in excel and work up some stats.

73

Mo' Power Mo' Power!

2014-03-28T22:36:00.000-07:00

When it comes to JT65A and many other digital modes, more power is not always the answer!

Do you need to know how little power is really needed to make that QSO in JT65A?

http://dwestbrook.net/projects/ham/dBCalc

Many times I've seen -1dB signals on my waterfall, and that's just too much power.

Many times I've seen over-driven signals killing the entire pass-band. You just ruined an entire 60 second over for everyone.

If you're getting -10dB or stronger signal reports you are using too much power.

So you guys out there that brag about using "...40W 3EL..." (and more!) to make a continental QSO you can do it on 5watts or less. I DX on an OCF wire up at 24 feet on 20 watts.

Anyone listening?

*crickets*

Great Morse Code Tutorial

2014-03-25T08:29:00.002-07:00

I've been learning Morse Code using the Koch method, and while it's the best method that works for me, I was getting board just repeating combinations of letters and would forgo my training sessions.

I decided to search the internet and see if there were any other methods to learn Morse Code and I stumbled across the CW Operators Club and their CW Academy. The next academy is not until Jan/Feb of 2015 (it's that popular and all booked up for this year!) and I couldn't wait that long to continue my training.

On their CW Academy Student Resources page I came across a link to a CW tutorial by Ron Brownstein of CWOps. It talks about using some program called Morse Code Trainer.

The Morse Code Trainer software is web/java based and is written by Stephen C Phillips. It follows the Koch principle but unlike other Koch software I have used before, they start introducing words using the letters you have just learned. In the first session alone you learn the words 'tea', 'tee', 'eat', 'ate', 'at', 'tat', 'teen', 'neat', 'ten', net, and 'tan'. How's that compared to boring repetitive strings of e, a, t, and n's?

So why is learning words important? Well for one, speed. If you only learn to recognize letters you limit your speed to how fast you can recognize individual letters. Once the speed gets up to where the dits and dahs run together you lose the ability to distinguish between the letters. If you learn to recognize the pattern or rhythm of the word instead of the letters you have just gained a lot of speed. The other important thing about learning words is proper Morse character spacing. If you only send letters equally spaced then that is what you get at the other end, a string of letters that you have to play a puzzle game with to form a sentence. But if you send words with spaces between the words you now have a proper sentence at the receiving end. The software starts you at 20wpm character and word spacing and I didn't find it hard follow along at that speed. So you can see already in session 1 you can copy and send words at 20wpm, a respectable speed for a beginner!

So what equipment have I been using to struggle through this learning process in place of CW Academy?

I am using my Yaesu 897D in CW mode but with BK turned off so I'm not transmitting and an old Vibroplex Original Standard bug (circa 1955) that belonged to my Grandfather. I have the sound from the radio headphone jack going in to the computer and have DM780 (Ham Radio Deluxe V5) listening to the audio so it translates the code into letters or more importantly words on the screen. I now know when my spacing is correct as sentences with words show up on the screen instead of a string of letters.

Using the bug to send along with Morse Code Trainer to learn the letters and words (that's how CW Academy does it) makes the process a lot more interesting for me and keeps me coming back for the training sessions. I may be too distracted by the bug as I find myself sending more than listening and my listening skills (at least to the live radio) seem to be lacking.

Session 1 as sent by the Morse Code Trainer software

Having said that however, I am only on session 2 in the learning, so my vocabulary is still very small and I think that has a lot to do with it.

So I'll keep plugging away with this Morse Code Trainer software and see where it goes.

73, and who knows maybe we'll CW on the air sometime soon!

Elmer Series - PROGRAMMING THE BAOFENG UV-B5 - 2

2014-03-15T17:07:00.000-07:00

PROGRAMMING THE BAOFENG UV-B5 - 2

In the previous post we discussed how a duplex repeater system works and the parameters that need to be programmed into the radio in order to access the repeater system, repeater output frequency, repeater offset, offset direction, and CTCSS tone. Now let’s program these into the radio.

I recommend you read through the steps first so you have an idea what the procedure entails. I’ll write up an abbreviated step guide further down to use once you get familiar with the process so you don’t have to find the actual step amongst all the text.

The first thing you need to do is to gather the required information for the repeater you are trying to access.

The following parameters are for the EAARS repeater located on MULE Mountain in Bisbee, AZ.

Output: 147.080

Offset: 00600

Offset Direction: +

CTCSS: 141.3

To make things easier right now I recommend we turn Voice Prompts on and set it to ENGLISH. Once you get familiar with the radio you will want to turn voice prompts off as it get annoying after a while. Voice prompts have their uses so turn them on when you want to use them.

Press the Menu button.

Rotate the VFO knob to Menu 09 (VOICE).

Press the AB button.

Rotate the VFO knob until ENGLIS is displayed on the screen and a voice says “ON”.

Now we are going to set the radio to VFO mode so we can type the output frequency into the radio.

1. Press the VM/Scan button to switch between memory and VFO modes. VFO mode is indicated when no channel number is displayed on the screen.

Now were going to type the frequency into the radio using the keypad. You will only press number keys, there is no need to enter any decimal point in the procedure.

2. Press the 1, 4, 7, 0, 8, 0 keys in that order. 147.080 should be displayed to the right of the arrow symbol on the LCD display.

Now were going to set the repeater offset amount.

3.       Press the menu button and rotate the VFO knob to menu 22 (OFFSET) is displayed.

4.       Press the AB button to edit that menu setting. The arrow should drop to the second line on the LCD display.

5.       Now press the 0, 0, 6, 0, 0 buttons in that order. 00.600 should be displayed to the right of the arrow on the LCD display indicating the value is ready to be changed.

6.       Press the Menu button to accept the value. 600kHz is now stored as the repeater offset.

Now were going to set the offset shift direction to +.

7.       Press the menu button and rotate the VFO knob to menu 21 (SFTD).

8.       Press the AB button to edit the menu setting. The arrow should drop to the second line on the LCD display indicating the value is ready to be changed.

9.       Rotate the VFO knob until a + is displayed on the LCD display.

10.   Press the menu button to store the value.

Now were going to set the CTCSS tone.

11.   Press the menu button and rotate the VFO knob to menu 12 (T-CODE).

12.   Press the AB button to edit the menu setting. The arrow should drop to the second line on the LCD display indicating the value is ready to be changed.

13.   Press the menu key again to switch between CTCSS, DCSN, and DCSI. If you have voice prompts on turn the VFO knob slowly until the voice says “CTCSS”. A number should be displayed that does not have an N nor an I after it.

14.   Rotate the VFO knob until 141.3 is displayed on the screen. If you are too slow in getting to 141.3 the radio may timeout and exit the menu system. If that happens, just repeat steps 11-14 again until you get to 141.3.

15.   Press the Menu button to store the value.

One other setting we’ll need to ensure is set correctly is the FM bandwidth. It needs to be set to Wideband (WIDE).

16.   Press the menu button.

17.   Rotate the VFO knob to menu item 28 and the voice prompt says “Channel Bandwidth”.

18.   Press the AB button to edit the menu setting.

19.   Rotate the VFO knob until the display shows WIDE.

We now have all the parameters entered into the radio, however we now need to store them in a memory channel so they are stored permanently. If this is the first time storing information to a memory channel I recommend you use channel 1, but you can store in any channel you desire. If you have stored other frequencies into memory make sure you know what the next empty channel number is or the channel number of a channel you want to write over.

20.   We first need to check that the frequency we entered earlier (147.080) is still displayed in the screen to the right of the arrow. If not, just press 1, 4, 7, 0, 8, 0 on the keypad again.

21.   Press and hold the VM/Scan button until the voice prompts says “Memory Channel” or a channel number flashes on the LCD display above the arrow.

22.   Rotate the VFO knob to the desired channel you want to store the repeater parameters too.

23.   Press the VM/Scan button again and the voice prompt will respond with “Confirm” indicating the information was written to the memory channel.

Now were going to check that the parameters were stored correctly in memory.

24.   Press the VM/Scan button until the voice says “Channel Mode” and a channel number displays above the arrow in the LCD display.

25.   Rotate the VFO knob until the channel you just stored the information in is displayed on the screen. The voice prompt will say the channel number.

26.   Ensure the LCD display indicates 147.080

27.   The W symbol should be displayed indicating the radio is in FM Wideband.

28.   The + symbol should be displayed indicating a positive offset shift.

To check the CTCSS, offset amount and shift direction we’ll need to enter the menu system to see them.

29.   Press the Menu button.

30.   Rotate the VFO knob to menu 22 (OFFSET) and the voice prompt says “Offset Frequency”.

31.   Ensure it displays 00.600.

32.   Rotate the VFO knob to menu to menu 21 (SFTD) and the voice prompt says “Frequency Direction”.

33.   Ensure it displays the + symbol.

34.   Rotate the VFO knob to menu 12 and the voice prompt says “CTCSS”.

35.   Ensure it displays 141.3.

If any of the values are incorrect you will have to exit the menu, change to VFO mode, and enter menu mode again and rotate the VFO knob to the menu number that contains the incorrect value and change it. Once it is changed you will have to follow steps 20 through 23 to save it again and overwrite the incorrect value.

That’s all there is to programming a repeater frequency into the UV-B5 radio and checking it’s accuracy.

Here are the steps in sequence without all the explanation included to make it easier to follow once you understand the steps above. If at any time the radio times out and exits the menu mode, just hit the menu button again and rotate the VFO knob to the desired menu number.

Entering the Repeater Information

1.       Press the VM/Scan button to switch to VFO modes

2.       Press the number keys to enter the repeaters output frequency

3.       Press the menu button and rotate the VFO knob to menu 22 (OFFSET) is displayed

4.       Press the AB button to edit that menu setting

5.       Now press the number keys to enter the desired offset

6.       Press the Menu button to accept the value

7.       Rotate the VFO knob to menu 21 (SFTD)

8.       Press the AB button to edit the menu setting

9.       Rotate the VFO knob until a the desired shift is displayed on the LCD display

10.    Press the menu button to store the value

11.    Rotate the VFO knob to menu 12 (T-CODE)

12.    Press the AB button to edit the menu setting

13.    Press the menu key again to switch between CTCSS, DCSN, and DCSI

14.    Rotate the VFO knob until the desired tone is displayed on the screen

15.    Press the Menu button to store the value

16.    Rotate the VFO knob to menu item 28 and the voice prompt says “Channel Bandwidth”

17.    Press the AB button to edit the menu setting

18.    Rotate the VFO knob until the display shows WIDE

Storing the Repeater Information in Memory

19.    Check that the desired frequency is still displayed in the screen to the right of the arrow. If not, just enter it again.

20.    Press and hold the VM/Scan button until the voice prompts says “Memory Channel” or a channel number flashes on the LCD display above the arrow.

21.    Rotate the VFO knob to the desired channel you want to store the repeater parameters too.

22.    Press the VM/Scan button again and the voice prompt will respond with “Confirm” indicating the information was written to the memory channel.

Checking the Stored Information

23.    Press the VM/Scan button until the voice says “Channel Mode” and a channel number displays above the arrow in the LCD display.

24.    Rotate the VFO knob until the channel you just stored the information in is displayed on the screen.

25.    Ensure the LCD display indicates the repeater output frequency

26.    The W symbol should be displayed indicating the radio is in FM Wideband

27.    The + or - symbol should be displayed indicating the desired offset shift

28.    Press the Menu button

29.    Rotate the VFO knob to menu 22 (OFFSET) and the voice prompt says “Offset Frequency”

30.    Ensure it displays the desired offset frequency

31.    Rotate the VFO knob to menu to menu 21 (SFTD) and the voice prompt says “Frequency Direction”

32.    Ensure it displays either the + or – symbol as desired

33.    Rotate the VFO knob to menu 12 and the voice prompt says “CTCSS”

34.    Ensure it displays the desired CTCSS tone

Elmer Series - PROGRAMMING THE BAOFENG UV-B5 - 1

2014-03-15T13:12:00.000-07:00

PROGRAMMING THE BAOFENG UV-B5 - 1

Programming the Baofeng UV-B5 from the keypad and radio menu system is relatively easy and can be accomplished without using PC software [edit]~~like~~ unlike[/edit] some of the other Chinese radios.

To understand why we are programming the radio with the settings we need to understand how a repeater operates.

A repeater is a radio system that retransmits signals that it hears. There are two distinctively different repeater types, simplex and duplex.

We’re not going to discuss simplex repeaters in this post other than to say they listen and transmit on the same frequency and therefore have to record the received signal and then retransmit the signal when the received signal stops. The simplex system takes twice as long to send a message than a duplex system.

The duplex repeater is more complex to setup and requires special equipment which increases the cost. However, it is the more popular system because it retransmits the received signal as it’s being received.

In order for a duplex repeater to work it needs to operate using two frequencies, one to listen to the received signal (repeater input frequency) and one to re-transmit the received signal (repeater output frequency).

In the US the difference ( repeater offset) between the repeaters input and output frequencies of the most common repeater bands are as follows:

6 meter (50MHz): 500kHz (negative offset)
2 meter (144MHz): 600kHz (positive or negative offset depending on repeater output)
70cm (440MHz): 5MHz (positive or negative offset depending on local conditions)

The repeater offset can either be shifted higher (positive offset) or lower (negative offset) from the repeater output frequency. For the 6 meter (50MHz) band the offset is usually negative. For the 2 meter (144MHz) band the offset shift is based on what the output frequency is. For the 70cm (440MHz) band the offset shift is determined by local conditions.

Because local interference or even a distant signal under the right conditions can interfere with the repeater causing it to transmit when it shouldn’t, most repeaters are set up to not transmit unless they also receive a special signal. The most common special signal used for this purpose is called Continuous Tone-Coded Squelch System (CTCSS).

CTCSS is a sub-audible (can’t be heard) tone that is transmitted along with the voice signal and when the repeater hears the correct tone it will retransmit the voice.

So now that we know the basics of how a duplex repeater works and some of the settings (output frequency, repeater offset, offset shift, CTCSS tone) that enable us to use a repeater system, let’s move on and discuss how to program these settings into the Baofeng UV-B5.

Elmer Series - PROGRAMMING THE BAOFENG UV-B5 - 2

Elmer Series - BAOFENG UV-B5 FM Hand Held Transceiver (HT)

2014-03-14T16:04:00.002-07:00

BAOFENG UV-B5 FM Hand Held Transceiver (HT)

NOTED ISSUES

1. (MAJOR) RF Burns on high power TX from battery contacts. It is worse when holding in left hand when thumb is used to PPT. Holding it in right hand and keying with fingers the battery contacts do not come in contact with my hand. Depending on hand size RF burns may be an issue using the right hand as well. Cover the battery contacts with some electrical tape, remembering to remove the tape before putting the radio in the charging cradle.

2. (MINOR) The UV-B5 is NOT a true dual band transceiver. It only has one VFO that is capable of RX/TX on two bands (136MHz-174MHz and 400MHz-470MHz). It has a feature called dual watch that switches between the two frequencies displayed on the screen, however it can not receive both frequencies simultaneously like a true dual band radio.

3. (MINOR) Is not legally part 90 certified (in the USA - no label) so it can not legally (in the USA) be used for commercial purposes.

4. (MINOR) It is not part 95 certified so it can not legally (in the USA) be used for FRS/GMRS/MURS.

5. (ANNOYANCE) When changing from one channel that has a ‘+’ repeater offset to a channel that has a ‘–‘ repeater offset the repeater offset symbol on the screen does not change to show a ‘–‘ symbol.

OTHER SITES

1. http://www.miklor.com/UVB5/

MENU OPTIONS

1.      STEP (Frequency Step): Used to set the step interval of the frequency increment when changing the VFO by either the VFO knob (channel knob) or the up/down buttons. 5kHz is the lowest step available but since most amateur repeaters end in 5 or 10 this is not an issue. Even if a station you are talking to is using a 2.5kHz step frequency you will still be able to talk to them. (5.00k, 6.25k, 10k, 12.50k 20.00k, 25.00k)

2.      SQUELCH: Squelch is used to silence the receiver when no signal is present. Use a higher setting if the squelch keeps opening and only static is heard. If you are listening to a very weak signal you may want to turn squelch off. (0 (open/off) through 9)

3.      SAVE (Save Mode): This is a battery saving mode. When on the receiver goes into standby mode and only checks to see if a signal is present every few seconds. When in Save Mode, because of how the feature works, you may not hear the first part of the transmission, usually the call sign (AJ7UU monitoring). (ON, OFF)

4.      TXPR (Power): Transmit power can be adjusted from low (1 watt) to high (5 watts). Use the low setting unless you are not being heard by your party. (LOW, HIGH)

5.      ROGE (Roger Beep): A roger beep is a tone that sounds on the radio and over the air every time you unkey the microphone. While it has its purposes (like using the HT as a repeater) it is annoying to most ham radio operators, so keep it off. (ON, OFF)

6.      TOT (Transmit Over Time): This setting is used to set how long you can transmit for without unkeying the microphone. This can be useful when working a repeater and you lose track of how long you have been transmitting for and do not want to transmit longer than the repeater timeout. Use it as needed. (OFF, 1M through 7M)

7.      VOX (Voice Operated Transmit): VOX can be used to transmit without pushing the PTT (push to talk) button. In VOX mode the radio will transmit when it senses a signal on the microphone input that is strong enough to trip the VOX circuit. The sensitivity of the VOX circuit is adjusted so that background noise does not trip the VOX circuit but your voice does. 9 seems to be the most sensitive and 1 the least. VOX can also be used when you want to use your radio (you will need two radios) as a repeater. (OFF, 1 through 9)

8.      BEEP (Beep Prompt): When this setting is on the radio will beep every time a button is pushed. Useful for visually impaired operation. (ON, OFF)

9.      VOICE (Voice Prompt): Used to select whether you want an English, Chinese, or no voice prompt when certain features of the radio are used. Not all features use the voice prompt. Very useful to confirm the memory channel you are selecting or when punching in the VFO frequency but can be turned off when silent operation is required. Also very useful for visually impaired operation. While the voice prompt is being played on the radio no received audio can be heard until the voice prompt is complete. (OFF, ENGLISH, CHINESE)

10. TDR (Dual Standby): This is the Dual Watch feature. While this radio is not a true dual-bander (does not have two separate VFOs), it has the capability to display two channels/frequencies on the screen and when dual watch is turned on it quickly switches between the two and stops on one when it is busy. When the channel has been clear for a few seconds it resumes switching between the channels. Dual watch is temporarily suspended when the radio in in scan mode and will resume dual watch when scan mode is stopped. Dual mode is useful when monitoring a repeater frequency and the FM call frequency (146.520). (ON, OFF)

11. R-CODE (Receive CTCSS Tone): Continuous Tone-Coded Squelch System or CTCSS and Digital Coded Squelch (DCS) are features to help filter radio traffic in a shared spectrum environment. See Wikipedia for more information on how CTCSS works. When the R-CODE is turned on and set to a specific tone, the receiver will emit audio only if the transmitted signal is sending the same CTCSS tone as set in the receiver. If the tones are different or no tone is being transmitted the receiver will ignore the signal and keep the radio squelched. Useful if you are using the radio as a repeater or want to limit what signals are heard. The people with whom you want to communicate or allow using the repeater must know what tone you are using. Most amateur radio repeaters use CTCSS and not DCS. While CTCSS is an analog tone, DCS is a digitally encoded stream. There are two modes of DCS operation, Normal (DCS-N) and Inverted (DCS-I). To set the tone from menu 11, use the A/B button then the menu button to select between OFF, CTCSS, DCS-N and DCS-I then use the rotary knob to select the tone you want to use. Recommended setting is OFF unless you have a requirement to filter traffic on the receiver. CTCSS tones and other settings can be stored along with a frequency in a memory channel. (OFF, CTCSS, DCS-N, DCS-I)

12. T-CODE (Transmit CTCSS Tone): When the T-CODE is set the specified tone will be sent when the radio is transmitting. The T-CODE will need to be set if you are trying to use an amateur repeater that has a receive CTCSS code set otherwise the repeater will ignore your signal. CTCSS tones and other settings can be stored along with a frequency in a memory channel. (OFF, CTCSS, DCS-N, DCS-I)

13. ABR (Backlight Select): When this setting is turned on the backlight will light up when any of the controls or buttons are pressed. Turn this feature off along with BEEP and VOICE if you do not want your radio lighting up or making noise when you operate it. Turning these features off will also conserve battery power. (ON, OFF)

14. PTTID (ANI Code): Used to identify a radio that is transmitting. When this setting is turned on and used on conjunction with menu items 15 and 16, a DTMF tone will be sent out when transmitting. A unique code should be programmed into each radio that you want to use this feature on to identify what radio is transmitting. This feature is only useful if you have a system that can decode and record the ANI code (along with a time stamp) or a live system that monitors/decode/displays the ANI code. Not a useful feature for amateur radio in general, but may have some use for SAR or EMCOMMS if there is a need to identify radio transmissions. This setting can be stored along with other settings in a memory channel while the ANI Code and the PTTID Mode are not. (ON, OFF)

15. ANI (ANI Code): This setting is where you enter the actual code for the radio. You can enter up to a 6 digit code using the numbers 0-9 and letters A-F. I think the E and F codes are the * and # symbols and may have special functions so I wouldn’t use them without testing if it works or not with whatever system you are using the radios on. Menu item 14 must be ON for this to work. (0-9, A-F)

16. PPTIDM (PPT ID Mode): Used to set whether the ANI code is sent at the beginning, end, or both beginning and end of each transmission. If set to beginning of transmission (BOT) the tone will be sent along with the voice and will stop as soon as the PTT is released. So if the PTT is briefly pressed then the complete code may not be sent. If set to end of transmission (EOT) the ANI code will be sent after the PTT button is released. The radio will extend the transmission time after the PTT is released and transmit the ANI code at that time so it does not interfere with the voice. This setting must be set to either BOT, EOT or BOTH along with menu item 14 being set to ON for this feature to work. (OFF, BOT, EOT, BOTH)

17. DT-ST: Used to hear the DTMF tone being transmitted when the PTT is pressed. Seems to only work when menu item 16 is set to EOT for PTTID. If you want to hear DTMF tones turn this setting ON, if not turn it OFF. (ON, OFF)

18. MDF-1 (LCD Display Line 1 Mode): Will either display the frequency you are operating on, the name of the channel (see menu item 27) you are on, or the memory channel number you are on in the top line of the LCD display. (FREQ, NAME, CHAN)

19. MDF-2 (LCD Display Line 2 Mode): Will either display the frequency you are operating on, the name of the channel (see menu item 27) you are on, or the memory channel number you are on in the bottom line of the LCD display. (FREQ, NAME, CHAN)

20. BCL (Busy Channel Lockout): This setting when set to ON will not allow the radio to transmit when the receiver squelch is open. The display will show BCL LOCKOUT error. (ON, OFF)

21. SFTD (Repeater Offset Direction): Used to set the repeater offset direction to `+’, `-‘, or OFF. Repeater offsets set whether the repeater input frequency is above or below the repeater output frequency. Depending on how the repeater you want to use is set up you will need to adjust this. Used in conjunction with menu item 22. (0, +, -)

22. OFFSET (Repeater Offset Amount): This setting adjusts the frequency offset by this amount in the direction set by menu item 21 above. (0-9)

23. SCANM (Scan Mode): When in scan mode this setting determines when, if at all, the scan will resume after stopping on a busy frequency/channel. The available options are TO, CO, and SE. In TO mode the scan stops on a busy frequency/channel and resumes scanning after a few seconds. In CO mode the scanner will resume once the carrier goes away. In SE mode the scanner will stop and will require a manual start. (TO, CO, SE)

24. TXAB (Transmit Priority): When used with dual watch, this setting is used to set which channel to transmit on when the PTT is pressed. If set to F1 the radio will transmit on the channel/frequency displayed on line 1. If set to F2 it will transmit on the channel/frequency displayed on line 2. If set to OFF it will transmit on the frequency/channel that the radio was displaying at the time the PTT was pressed. This can be useful if you are monitoring two channels but only want to transmit on one. (OFF, F1, F2)

25. REV (Reverse Duplex Mode): When the reverse duplex mode is turned on it swaps the repeater input frequency and settings with the repeater output frequency and settings that are stored in the selected memory channel. With REV turned on the radio is monitoring the repeater input frequency and will transmit on the repeater output frequency. At this time I do not know of a good reason to use REV. (ON, OFF)

26. STE (Squelch Tail Elimination): Used to curb the static crash heard after a transmission ends. Used between radios that have the capability. Not useful for repeater use and may cause problems. Best to leave it off unless you know for sure it’s safe to turn it on. (ON, OFF)

27. NAME (Name of Channel): Used to add a name to a memory channel. Used in conjunction with menu items 18 and 19. Can be stored in a memory channel. (A-Z, 0-9, /, _, +, -)

28. W/N (Wideband/Narrow Band): Selects between narrow band FM (2.5kHz) or wide band FM (5kHz). Use wide band FM for amateur use as it has better signal to noise ratio for weak signal work. Narrow band is used for FRS /GMRS/MURS but legally you can’t use part 90 certified radios for FRS/GMRS/MURS which are part 95 services. In an emergency situation use the radio on whatever frequencies you need to.

29. COMP (Audio Companding): Supposed to help with audio quality and back ground noise. When turned on it affects both transmitted and received audio. I noticed it does clean up the background hiss but also reduces the overall audio level. On a good full quieting signal it is probably not needed. When I tuned into a distant repeater with a lot of background noise the audio was reduced as much as the background static so I’m not sure how well this feature works.

SPECIAL BUTTON SEQUENCES

1.      RESET (VFO/ALL): With the UV-B5 turned off, hold the Menu button and turn on the radio. Once the radio powers up you will see the reset options. Either rotate the VFO knob or use the up/down arrows to switch between VFO/ALL. VFO will just reset the VFO but ALL will erase all the memory channels.

2.      SCAN: From either VFO/Memory/FM modes, press the menu button then the VM/Scan button. The scan will stop on a busy channel/frequency and resume scanning depending on what menu 23 is set to.

3.      LOCK/UNLOCK: Press and hold the Menu button to lock and unlock the radio.

4.      DTMF Tones: DTMF tones are used for many purposes in Ham Radio. Basically DTMF tones are used to send commands to a system in order to accomplish some function. Some common functions in a repeater system that may use DTMF tones are, enable/disable the repeater, enable the phone patch and dial a phone number, and enable the internet link and dial up a remote system. To send DTMF tones on the UV-B5 radio, press the PPT button and press the buttons on the radio. The following buttons are assigned the DTMF tones as follows:

· Menu: A

· ^: B

· v: C

· AB: D

· 0-9: 0-9

· VM/Scan: *

· FM: #

New Call - AJ7UU

2014-01-28T10:05:00.000-07:00

I decided I needed a 7 area call sign. So I applied for a vanity of my old call and changed the 4 to a 7.

So if you worked me as a 4 you can work me again as a 7.

73

Tim

Temporary Mast Install

2013-12-15T14:37:00.001-07:00

I put up a 20ft mast today and now am running a somewhat inverted V OCF-40. For now it's anchored in a 5 gallon bucket of rocks and guyed with the antenna elements and coax cable. Next payday I'll rent an auger and make a hole and cement in a base for it and run some real guys. I should be able to get it up to 32ft then, that's my goal anyway.

CW Ops Hatin' on Some JT65 Ops

2013-12-15T13:32:00.000-07:00

For some reason the contestants today decided to CW all over 28.076MHz. Not pretty. One CW Op even had some drifting. With all the band-space on 10m why operate CW here? :/

Field Day 2013

2013-06-23T07:03:00.000-07:00

Elevation of Field Day Site

I survived Field Day and ended up running a 1B at 50W for a total QSO count of 13 (had one dupe, how I don't know with that few contacts) which totaled up to 26 points (+100). I found that my laptop and especially my USB-Serial port made so much noise that they were useless for digital modes. I'll need to do some serious investigation and/or purchase new equipment to solve this major problem. Once I disconnected the USB-Serial port I could see many signals on the screen but it was still noisy. Then I removed the charging cord and all the noise went away and was left with a black screen full of PSK31 signals. I tried to answer a few CQs on 20m but at 5W PSK Reporter only showed a couple of stations heard me.

PSK Reporter

My antenna was not where I wanted it but the rope I brought to hoist it up in the trees was so sun rotted that the bark on the pine trees tore it up so bad I couldn't hoist the rope to pull the antenna up. I settled for some smaller trees about 10 feet and propped the middle of the OCF up with a 10 foot branch someone had hauled into camp for firewood.

OCF DX-40 at 10 Feet

20m SSB was poor when I tried so I switched to 40m and tried to answer some CQs. Lo and behold I had people answer me! I worked 40m SSB until conditions started to fade and my battery wouldn't handle 50W anymore.

Working 40M SSB

Next year I need some para-cord and fix the computer noises to have a successful Field Day on 5W Digital for a better score.

I think for my QTH I need a separate shielded shack and filtered power to have quiet conditions.

Hope to see you on the air!

73

AJ4UU

Field Day 2013

2013-06-10T13:49:00.003-07:00

I'll be operating from the Huachuca Mountains on 22 June from the start of the event (11am local) until we get tired (late afternoon/early evening).

Hope to see you on the air!

73

AJ4UU

Disaster Prepardness QST

2012-08-15T10:52:00.001-07:00

I highly recommend the September 2012 issue of ARRL QST magazine for disaster preparedness communications.

It's full of articles that pertain to emergency communications preparedness and operation.

You should be able to order a copy at http://www.arrl.org/qst.

73

AJ4UU

Radio Communications Systems During Crisis Situations (Modes and Modulation)

2011-09-28T06:50:00.002-07:00

What are the best modulation methods to use?

Modulation is the process of attaching or sending the data to be communicated along with the carrier wave. Properties of the carrier wave are manipulated by the modulation process so the carrier changes as the data changes. The carrier wave is the transmitting frequency of the radio. It’s created in the Variable Frequency Oscillator (VFO) and then modulated by the desired method and amplified in the final stages so there is enough power radiated off the antenna.
The first modulation method, if you can call it that, was continuous wave or CW. The telegraph key literally turns the transmitter’s carrier frequency on and off. There really was no modulation other than turning on/off the carrier frequency. By turning the carrier on and off using a prescribed code (Morse code, a combination of short and longer times the carrier is turned on spaced with the carrier off) the data could be sent out the transmitter. Since the only energy being sent is radio frequencies and the human ear can’t hear them we need to figure out a way to make it audible to the human ear. The receiver has built in another oscillator called a Beat Frequency Oscillator (BFO). The BFO usually outputs from 650 to 800 Hz. When the receiver’s VFO frequency is tuned exactly to the transmitter’s VFO frequency (the carrier frequency) the receiver’s BFO frequency gets set to an audio amplifier and then to a speaker or headphones so we can hear it. As the receiver tunes away from the transmitters carrier frequency the BFO frequency changes in pitch either up or down depending on which way the receiver is tuned, up or down from the transmitters frequency. Using a wide CW filter one can hear many different signals at different BFO frequencies at once. With a little practice and “brain tuning” (using your brain to concentrate on the one pitch and “tune” out the others this method works well. By using a narrower filter one can physically tune out more of the unwanted signals making copying easier. Because the transmitter “carrier” doesn’t actually carry any information that could get scrambled or not received in the noise and the data is based on only receiving or not receiving the carrier (the receiver actually makes the data intelligible) it is a very good method for low power or poor propagation conditions. If the receiver can hear the transmitter carrier going on and off then it makes a sound to match in the speakers.
Soon after CW was invented people wanted to try to actually modulate the carrier to see if it could carry audio created by a person’s voice. In the early days the easiest way to modulate the carrier was to change the amplitude or power of the carrier. This modulation technique is called Amplitude Modulation or AM. When modulated with sounds of a human voice the power of the transmitter was changed which superimposed the sound onto the carrier. Now we have a true modulation in the sense that there is actual data on the carrier instead of the carrier just being turned on and off to a predetermined code. So now the receiver listens to the AM carrier and demodulates (the opposite of modulation) the audio from the carrier and sends the sound to the audio amplifier and speakers. When transmitting using AM the carrier is on all the time or 100% duty cycle even if you are not talking. Because of this the transmitter pulling its fully rated power from the batteries every time the transmit key is pressed. Also because it’s a 100% duty cycle mode the amplifier’s power has to be reduced (or built about 4 times more powerful to handle the load) so as not to overheat and burn up the amplifiers transistors. What this means is modern transmitters rated at 100 watts are rated this high for a lower duty cycle mode like SSB and the power for AM has to be reduced to 25% or 25 watts. So to transmit AM at 100 watts we’d need a 400 watt amplifier.
After AM was invented, people look at ways to improve on AM so it wouldn’t waste as much energy when transmitting. One way to improve AM was to not send the carrier signal unless sound was actually being modulated, or an even better way was to not send the carrier at all. So if we don’t send the carrier at all how is there a signal to demodulate at the receiver? When voice modulates the amplitude of the carrier it creates what are called sidebands where the actual data is stored. Data is stored on a small section about 3.5kHz above and below the carrier frequency. If we could suppress the carrier frequency and only send out the data in the side bands then we could double our power output. This mode is called carrier suppressed double side band or DSB for short. It maintains the full bodied audio of the AM signals but the carrier is suppressed at transmitted and only the frequencies of the side bands are transmitted.
Now the magic of sideband is for our brains to understand the data we really only need to hear half of the DSB signal. So a way was invented to suppress one of the sidebands and only transmit the other. Now were up to a whopping four times power output over AM. This method of modulation is called carrier suppressed single sideband or SSB. Since we can choose which side band to transmit when we transmit the sideband located above the carrier frequency it is called upper side band or USB and when we transmit the sideband located below the carrier frequency it is called lower side band or LSB. Because we hear only ½ the original voice the quality is not as good as AM or DSB but it is still intelligible and can actually get through the noise about 50% better than AM because of the power increase.
So now that the methods of improving modulating the amplitude of a carrier had been fine-tuned people began to look at other methods of modulation. Another parameter of a carrier wave is its frequency. If we change the frequency of the carrier with our data then we are modulating the frequency. This method is called frequency modulation or FM. FM is a 100% duty cycle mode as we're not changing the output power of the transmitter as we speak it is constant. The amount the carrier changes frequency is called deviation as the frequency deviates from the carrier frequency as it is being modulated with the data. Too much data or a loud voice will cause the frequency to over deviate and the receiver which has been designed to only look for a certain frequency fluctuation will not hear all the data the sound will be distorted. This also causes interference to the adjacent frequencies since the over deviated signal will encroach into their space. Because FM changes the carrier’s frequency the width of the signal is much wider than SSB. 15 kHz for most amateur radio applications and 75 kHz for professional FM radio stations. Since the bandwidth requirements are more, FM is not allowed on any bands below 10 meters. One nice feature with FM is called the capture affect. This allows the receiver to only tune in the stronger of the received signals at the same frequency and helps eliminate background noise. This causes a condition called full quieting since the capture affect locks on to the transmitter’s frequency and all the weaker signals (noise) are filtered out. This is why this mode was used for FM broadcast stations.
One other parameter of a carrier signal that can be changed is its phase. This is mode works very similar to FM but instead of changing the frequency the phase of the carrier is shifted forward or backwards with the data. This method is used mostly with UHF and above commercial applications like wireless WiFi routers and cell phones.

What are the best modes (voice, digital, Morse code) of communication?

Like frequencies, different modes work better than others at different times. Though when propagation is at its best all modes work equally, so I guess it should be said during times of poor propagation some modes work better than others.
The difference between modulation and modes:
Modes of communications are not the same as modulation and can be confusing to the novice. Modulation is how the carrier frequency is changed to carry the data being sent, whether it’s voice, Morse code, or a digital signal. The communications mode is how the data is formed before it is modulated onto the carrier frequency. The mode that is often confused with modulation is Morse code. Morse code is just that, a predetermined code that humans devised to present the letters of the alphabet along with punctuation and other radio specific terms so that is can be sent via the carrier. CW is the modulation method. The carrier in CW is modulated by turning the carrier on and then off in short and shorter increments. The receiver then emits an audible tone every time it receives the carrier frequency being turned on and off at the transmitter. Since Morse code and CW are used extensively together the terms CW and Morse code are used interactively.
CW and Morse code:
With CW no data is modulated on the carrier other than the sequence that the carrier is turned on and off therefore the data cannot be interfered with during propagation. The receiver generates the audible signal when it hears the carrier so propagation just has to be good enough for the carrier to be heard in the noise. A good ear can easily pick out the tones and with the advent of digital signal processing a digital filter can be implemented to amplify the tone while reducing the noise. Because of how CW works it makes for a fine “mode” of communications. :)
Single Sideband (SSB):
Single sideband or SSB is a modulation method that was first used to modulate a person’s voice onto the carrier. So SSB is the modulation and voice is the mode. SSB voice needs better propagation than CW to be “copied” as the voice (data) can be interfered with during propagation and the ear can’t interpret the sounds as easily in the noise. However during times of good propagation voice is easily recognized so untrained operators can easily copy it. Also no accessory equipment is needed to copy it.
Computers and digital modes: Text messaging of the radio world.
Ever since the invention of the Personal Computer, Amateur Radio enthusiasts have invented ways the two can be used together. Everything from software to log radio contacts, designing radios and antennas to controlling and modulating the transmitter have been devised. Earlier modes such as RTTY used a Terminal Node Controller or TNC which is a modem very similar to a telephone modem used for dialup internet access. The TNC sat between the computer and the radio and converted signals (text typed on the keyboard) from the computer to sounds that modulated the carrier. The TNC at the receiver converted those sounds back into signals the computer would recognize and display as text on the screen. Very early RTTY stations used a teletype which was a keyboard and a print mechanism that printed the received code onto a strip of paper.
When soundcards came onto the scene methods were devised where the computer encoded the data as sound and then that sound was hardwired to the transmitter microphone input and modulated on the carrier via SSB. Again the opposite occurred at the receiver and text was displayed on the screen.
The popular soundcard modes include RTTY, BPSK31, BPSK63, BPSK125 and BPSK250. QPSK modes are also available. Some PSK modes include error detection/correction methods.
The PSK modes increase in bandwidth as the number goes up thus decreasing transmission time (more characters per second can be sent) but are affected more by poor propagation. BPSK31 with a bandwidth of 62.5 hertz is a (very) narrow bandwidth mode and can transmit at about 50 words per minute, as fast as a human can type. In a well-disciplined environment 32 BPSK31 conversations could happen in the same space required for one 2.4kHz SSB voice conversation. Realistically about 20 BPSK signals are possible due to the need for space between the signals because of over modulation and frequency drift/creep.
BPSK31 is a very viable low bandwidth mode and I have had many contacts on 20 meters to USA and Europe during solar minimum on less than 50 watts and at times 25 watts with “a not so optimal” antenna setup. With a decent antenna setup and good propagation 5 watts can work the world. With a 100aH battery you could transmit all day at 5 watts.
Other soundcard modes:
Other soundcard modes that work well during periods of poor propagation are Olivia, MT63, MFSK8 and MFSK16.
HF/VHF packet is used to send messages by a store and forward method. Automatic Position Reporting System (APRS) uses packet to report the GPS position of the transmitter and to send any messages the operator types in. Any signals received by an APRS repeater are sent back out. If these signals are again received by another repeater then they are sent out also. This receive/re-transmit scheme sends the packets of data over a wide area. Internet gateways are also incorporated so data can be received worldwide. APRS can be used without GPS for sending messages and of course one can set up a receive only station also.

Radio Communications Systems During Crisis Situations (Frequencies)

2011-09-14T21:47:00.000-07:00

What are the best frequencies to use?

This section deals with long distance propagation via the ionosphere and does not apply to local line of sight/point to point communications. Except during an extreme solar storm line of sight comms should work with no issues. We're also talking reliable communications that are available 90% of the time or better. Other bands may open up during atmospheric events but it varies too much to be considered reliable.
The trick to choosing a frequency is to know which ones are going to work at certain times. The times can be divided into day/night/twilight, solar minimum/maximum, all four seasons, and even location as in high latitudes (near the poles) mid latitude, and equatorial latitudes (near the equator). Even where (how far) you are trying to communicate with will dictate what the best frequency to use is.
A combination of these factors will determine what the Lowest Usable Frequency (LUF) and Maximum Usable Frequency (MUF) will be for a given situation. It can be quite complicated when taking in all the parameters that go into calculating the LUF/MUF needed to talk to another region on the earth.
In general radio waves between the LUF and MUF reflect of the ionosphere. Radio waves below the LUF are absorbed by the ionosphere and radio waves above the MUF pass through the ionosphere into space. The trick is to know what the LUF and MUF are. But in a SHTF situation that information may not be available to you. Even the parameters used to calculate the LUF and MUF won’t be available to you. So how do we figure out what frequencies will work and what ones won’t? We don’t want to waste precious battery power transmitting on useless frequencies.
So how does all this frequency stuff work anyway? The sun produces ultraviolet (UV) light and that UV light is captured/filtered/absorbed by the upper levels of the atmosphere or ionosphere. The UV light hits the upper atmosphere and the atoms up there temporarily loose an electron and then recombine with that electron later. The separating and combining of electrons is a continual process as long as the UV light is present. These free electrons are called ions, hence the name ionosphere. During the day (or more precisely on the sunlit side of the earth) the UV light forms more ions. During the night or on the shadow side of the earth there is no UV light so there are fewer ions. During periods of low solar activity the UV light levels are even lower and the density of free electrons is also low. During periods of high solar activity the UV levels are quite high and the free electron density is high. The more ions present in the atmosphere the higher the MUF will be. Think of the ion density like a net, the more ions the smaller the openings in the net. The smaller openings keep the higher frequencies (due to their smaller wavelength) from passing though into space and they bounce back to earth.
As the UV light excites the atmosphere on the sunlit side of the earth the ions created separate into layers. On the shadow side of the earth the few ions that are there combine into fewer layers. The upper layers (F1 and F2) during the day make long distance communications possible on the higher HF frequencies. Again the more free ions the higher the MUF will be. During daylight hours the LUF is set by the lowest of the layers called the D layer (remember D for Day) that actually absorbs all the frequencies below the LUF. So during the day ionosphere propagation of the low frequency waves is impossible, no matter how many watts of power you force into it. After sunset the D layer quickly (thankfully) dissipates so long distance communications is now possible on the lower frequencies. The F1 and F2 layers combine into a single F layer.
In the region of the atmosphere where the sunlit and shadow areas meet (twilight/sunset/sunrise on earth) there is a collapsed combination of all the layers and they form a little conduit. This little conduit traps the radio waves and sends them all along the conduit bouncing them to the earth all along the way. This little conduit is also called the grayline. So what happens is anyone passing through the grayline can communicate with someone else that is also in the grayline at another location on earth. So communication is possible during sunrise on one side of the earth to somewhere during sunset on the other side of the earth. So don’t rule out twilight hours for long distance communications.
Also remember even after dark when the D layer dissipates, the LUF will be higher towards the west (sunlit areas) that to the east (areas already in the dark). This is because the D layer still exists for the areas in the daylight and will absorb the lower frequencies while the D layer is gone for the areas in the dark. So when trying to talk to areas still in sunlight a higher band may be needed while talking to areas already in the dark maybe possible on a lower band.
The peak for this solar cycle is from 2013 to 2016, a good 3 years of higher frequency band openings. Right now in 2011 we are about ¼ of the way to the peak. The downslope of the solar cycle is usually less steep than the upslope which is a good thing. It means the peak will arrive sooner and linger longer.
A few caveats I need to mention during solar maximum. Once the sun really begins to pick up activity there can be solar storms from X-ray Flares or UV Coronal Mass Ejections (CME) that can wipe out all communications for a period of time, usually just a few hours but sometimes days. These storms can be heard as really loud white noise or static on the radio. 10 meters really gets noisy during a CME and you can actually hear the wave waver in intensity as the CME passes over the earth. Also a large X-ray or CME burst can cause inducted power spikes on really long antennas. This is what happens to our power grid during a solar storm. Also these storms can wipe out satellite communications and even damage satellites because they are not protected by the earth’s electromagnetic field.
So in saying all that we really haven’t discussed what frequencies to use when only to determine higher frequencies work better in the day and lower frequencies work better at night.
Long Distance Comms (HF):

During solar minimum 20 meters is about the highest frequency that can be used during the day and usually only with high reliable modes like CW and PSK. During solar maximum up to 10 meter and even 6 meters can be used during the day and since it takes a little while for the ions to recombine 20 meters can be used for a while after dark. SSB voice can be used easily during solar maximum.
At night during solar minimum the lower frequencies work well up to 40 meters. During solar maximum all the low frequencies through 20 meters work well even 10 meters in the early evening. Noise may wipe out 160 and 80 meters at times. Electrical storms (lightning strikes) can cause very loud crashes of static, so be careful if you are wearing head phones and listening to the lower frequencies. It’s quite startling and painful.
So you can see that the more viable bands are 40 and 20 meters. That’s why they are called workhorse bands. If you could only have two HF bands these would be the ones to have. And these bands are where I’d invest more in my antennas.
At a minimum these antennas should be at least ½ wavelength high to get the take-off angle below the critical takeoff angle so it will skip. They do not need to be higher than 1 wavelength and trying to doing so will only use valuable resources that could be used elsewhere.

Local Comms (HF):

Using a Near Vertical Incidence Skywave (NVIS) antenna (covered under the Antennas section)
I’d use 80 meters at night and 40 meters during the day. During solar minimum 80 meters is not absorbed as much during the day. During solar max 80 meters is wiped out during the day. 40 meters is open at night most of the time.

To sum it all up:
80 meters and below work during the night.
40 meters and up work during the day. 15 and 10 meters need some solar activity to open up; dead during solar minimum for the most part and dead at night. The current solar peak is slated from 2013 to 2015.
The more active the sun is (further into the solar max peak) the higher the frequencies we can use. Up to 6 meters is possible.
Local point to point or line of sight communications are not affected by solar activity except during solar storms.
Now the final part to this is what specific frequency should I transmit on?
Other than listening up and down the band for someone to talk to there are specific frequencies on each band call calling frequencies. There are calling frequencies for different modes. A good source can be found here. Once you establish a contact on the calling frequency you should move from that frequency to carry on the conversation.
During a crisis situation "networks" or nets are established on the bands to handle emergency traffic. There are also established nets like the Maritime Mobile Service Network (MMSN)on the 20 meter band at 14.300MHz that run from 1600 to 0200 UTC or on 21.412MHz that run from 2200 to 2400 UTC. The MMSN is for ships that need to check in to give position reports or report emergencies. All kinds of Nets and their times and frequencies can be found here.

Radio Communications Systems During Crisis Situations (Antennas)

2011-09-14T09:06:00.000-07:00

This is part 5 in an ongoing series on radio communications during a crisis event.

What type(s) of antenna should I have?

Antennas are the best and cheapest way to increase RF signal strength and they don’t require any more resource power to provide the amplification. One can easily double, triple, and even quadruple the effective radiated power out of the antenna. So quite easily you can amplify those 5 watts of transmitter power into 20 watts at the antenna. Remember the inverse square law where doubling the output power only increased received signal strength by 25%? By quadrupling the power we have increase receive signal strength by 50%. So the receiving end can hear us 50% better!
How is this possible with no extra resource power consumption? Quite simply by the way the antenna materials act with the RF energy. A typical dipole antenna in free space radiates the energy equally in all directions. Since the receiver’s short path is in only one direction that’s a lot of wasted energy going in all other directions where it’s not needed. What if we could turn all that wasted energy in the direction of the receiver so they get ALL the radiated power from the antenna? Well we sure can.
RF energy reacts with metal objects that reside in an area a certain distance (based on the frequency) from the main radiating element. If a longer (about 5%) element is placed to one side of the radiating element it tends to reflect the energy in the opposite direction. This element is called a reflector. If another element (5% shorter) is placed on the opposite side of the reflector it will tend to pull the RF energy in the same direction. More than one (incrementally) shorter element can be placed in the directed path further refining the RF energy into a well defined beam of energy. These elements are called directors. The reflector and director elements are passive parasitic elements that are not directly connected to the radio coax antenna cable. They do not require any power resource to accomplish the reflecting and directing of the RF energy. They accomplish this task by their parasitic nature by robbing the RF energy pulling it toward them and thus in a specific direction. If the reflector and director elements are all in the same plane then all the energy is concentrated into a beam. The more directors the more concentrated the beam becomes though with diminishing returns. Because the RF energy is formed into a beam, these antennas are called beam antennas or Yagi antennas after the inventors Uda and Yagi. The old TV antennas are also beam antennas but are of a different design. They are actually log periodic and have a wide frequency range and mainly used for receiving only. Amateur band antennas are not as wide a frequency range and usually limited to a large portion of the band they were designed for.
The lower the radio frequency the longer the antenna elements and the higher the frequency of the radio wave the smaller the element lengths. This makes constructing large element arrays at lower frequencies more difficult and expensive due to material costs and structural framing to hold all the elements in the same plane. However higher frequency antennas can support much larger element arrays again due to material costs and structural requirements. This makes it easier and less costly to make a higher gain VHF or UHF antenna than to make a high gain HF antenna. Typical element lengths are approximately half the wavelength. So an 80 meter element will be about 40 meters long, a 40 meter element will be about 20 meters long, a 20 meter element will be about 10 meters long and 10, 6, 2 and 70cm elements will be 5, 3, 1 meters and 35cm long respectively. These element lengths are approximations and the true element length depends on the actual frequency being transmitted but it does give one an appreciation of how large an antenna can get for the lower HF bands. Practically speaking, when building your own antenna out of scrounged parts after TSHTF, it would be difficult to build a gain antenna for 80 or 40 meters. For these bands a simple dipole is hard to beat cost and construction wise. A 20 meter beam antenna might be practical and for 10 meters and higher it’s quite practical and even preferred over a simple dipole since the structure can now be supported by one supporting post rather than two for a dipole. For the added cost in materials and ease of building it just doesn’t make sense to not use a beam gain antenna at the higher VHF/UHF frequencies.

How high should the antenna be?

Antenna height is a much debated topic when it really shouldn’t be if you know all the factors about antenna height. What I think usually happens is someone asks someone how high their antenna should be and the answer given is only one of many possible answers. This then starts the heated discussions I’ve seen in forums and at Ham meets where each is arguing that their height is the best (and for their application it most probably is) but it won’t help the other guy that is trying to accomplish something different with their radio.
So let’s start with a little theory and hopefully it will explain that the best antenna height depends on where you are trying to communicate to.
Remember the question about which antenna should I use there was the isotropic di-pole antenna that radiated that precious RF energy equally in all directions and wasting it? And by putting parasitic elements in an array we could form the energy into a more compact beam and direct it at our receiver? Well we can do the same thing by bringing that isotropic di-pole down to earth and having the earth act as a parasitic element. What this does (and I’ll try to explain this without a picture) is to squish the round sphere of energy so it no longer sends energy toward the ground or toward the sky but only out to the sides of the wire element. By directing the energy wasted in the air and ground we’ve almost doubled the energy going out the sides. It’s not quite double as the beam width is still too wide and going in 2 directions. I’ve never done the calculations myself but it has been calculated about 2dB gain (3dB gain is double power) can be had over an isotropic dipole.
If the dipole is set about ½ wavelength above ground the energy is concentrated into a beam that points at about 30 degrees (for simple math) into the air. This angle is called the takeoff angle. If we raise the antenna to 1 wavelength the beam splits into 2 separate beams the lower one at 15 degrees. As the antenna is raised the beam splits into more beams with tighter patterns and the angle of the lower beam is lower, about ½ the previous angle per wavelength in height. Now in between each beam is an area called a “null” area that will reduce the signal strength of any RF energy coming in at that angle.
These beams at different angles shoot into the sky and the beams that point higher will bounce at a less of an angle angle in the sky and land at a closer distance than the lower angled beams. The lower angle beam thus can travel further distance across the ground in one bounce (hop). Each hop chews up some signal strength so to talk long distances it’s best to do it in the fewest possible hops.
Now remember the nulls? The angle of these nulls will produce mini skip zones where the signal strength will be less at the distant receiving and could be so much less at a specific angle so the signal may not be heard. For an antenna at ½ wavelength with the one wide beam at 30 degrees there will be a significant initial skip zone then several progressively smaller skip zones because the bouncing beams will scatter a little causing the energy to spread out. After several hops the skip zones will be minor however if for some reason the beam of energy is only received at a certain angle and the height of the receiving antenna is such that there is a null at that angle the signal will be weak or unreadable.
Set the transmit antenna at 1 wavelength and now there are 2 beams one that bounces closer and one that bounces further. We now have 2 skip zones but after a few hops of beam spread they are greatly reduced because of the overlap. Raise the antenna further and you have more beams, more nulls, but lower angles for longer hops. The same happens for a beam antenna only the elevation patterns take on a more complex beam and null pattern with the lowest beam being the strongest and many smaller beams and quite wide nulls in places.
So armed with this knowledge you can see why there might be some heated discussion going on about antenna height. For one person talking to Europe his antenna height may be perfect but someone a little further away may not hear Europe very well. And vice versa the guy that can hear Europe may not hear Japan but the guy that can’t hear Europe may hear Japan just fine. If either one could change the antenna height then they could hear the other locations just fine also.
So what’s the correct answer? Antenna height will need to be calculated for your transmitter location and receiver location. Most people with simple setups put the antenna at ½ wavelength and leave it. That’s what I did in Florida. Actually the antenna was at 20’, not quite ½ wavelength for 20 meters which is what I usually transmitted on. It was a bit of a “sky warmer”. Outside the initial skip zone I could talk all up the east coast on the first hop and all of Europe and some of Eastern Russia on the second hop. Even though the wide beam pattern at only one angle may not be as strong as the more concentrated lower beam of a dipole at a higher elevation I had enough power for 2 hops and no receiving nulls. That was during solar minimum too.
One important area we briefly mentioned, the initial skip zone, is a very important zone is a SHTF situation. At HF frequencies it’s too wide to cover with line of sight VHF so there is this zone around us that we can’t hear, literally. From my receiver in NW Florida I could not hear Georgia, Alabama, Mississippi, Arkansas, Louisiana, and most of Florida. Extend that circle around into the Gulf of New Mexico and that’s how much area around a receiver in the Midwest would not be able to hear. That’s almost half the country. So what can we do to remedy that problem?
Remember the dipole at ½ wavelength radiated the energy in beams off the side at about 30 degrees and when raised these beams multiplied and pointed lower in the air? If you do the opposite the beams actually point higher into the sky to where they become one beam pointing straight up and less RF energy is radiated at the lower angles. The antenna at this height is horrible for long distance communications since the energy is pointing straight up and there is no skip. This antenna is called a “cloud warmer” by some and meant in a bad way when trying to communicate long distance. The term used for this antenna when used for its practical purpose is Near Vertical Incidence Skywave (NVIS) antenna. Its practical purpose is for communicating to people located in the skip zone. The energy is not so much reflected like a beam hopping over the Atlantic, but scattered in all directions (backscatter) filling in the skip zone void. A NVIS antenna is also great when you station is located in mountainous country and the takeoff angle of a higher antenna points right into the side of the mountain.
So now knowing this much information it seems like you would need a of couple antennas to cover long distance and the skip zone. That would be the best idea, a beam antenna at a calculated height to cover the long distance areas of interest and an NVIS dipole to cover the skip zone. If that’s practical for you and you can afford to hang a HF beam higher than ½ wavelength then it may be your answer. However for OPSEC reasons I’d not like to advertize I had communications to everyone who drove by. A wire strung between two poles is harder to see from a distance than a big HF beam on a tower.
My choice STSHTF would be a single Off Center Fed (OCF) Di-Pole cut for the 80 meter band stretched between 2 masts 30-60ish feet off the ground and on a pulley system so the height of the dipole can be adjusted for long distance or skip zone communications. The OCF dipole is a special dipole pole that is not fed in the center but off center a bit. By doing that the impedance match is now off by 4 and the antenna becomes unbalanced so to feed it with coax take a couple of extra components called BALUNS. I’ll not get to technical on how the antenna works, but this antenna not only radiates well on 80 meters but also quite well on 40, 20 and 10 meters. The radiation pattern is not quite the same as the standard dipole nor is the takeoff angle the same when transmitting on a frequency off the 80 meter band. But taking all that into account this makes a wonderful single antenna that covers 4 HF bands. You can cut the OCF for 160 meters but the wire is so long that it needs a center support as well. Now it becomes more expensive to support, needs more surface area to stretch out and more work involved to raise and lower it. During SHTF situations my bet is communications will be concentrated on the 3 work horse bands, 80 (NVIS – local night comms), 40 meters (NVIS – local day comms) and 20 meters (30 to 60’ - long distance day comms), since simple antennas for these bands are easily deployed due to their smaller size and height requirements.
One other antenna that I haven’t mentioned yet is the HF vertical. If you have the time to prepare beforehand then a tall vertical makes a decent antenna also for long distance work. They are more complicated, need a foundation and heavier materials to support it and many wires strung out underneath it for a ground counterpoise. I don’t recommend this antenna if you are going to construct it ATSHTF. Also the vertical has a low take off angle making it a poor choice for local comms.
So my final recommendations for SHTF antennas are:
An 80 meter OCF dipole stretched between two poles or trees 33 or 66 feet in the air on a pulley system to raise or lower it. This will cover 80/40/20/10 and even 6 meters. You will need 140 feet of available ground to stretch it out.
A 20-15-10 meter triband yagi at 30ish feet. You can also add 6 meter parasitic elements to add 6 meters to the antenna.
A copper pipe (or whatever metal you can scrounge ATSHTF) J-Pole cut for each of your VHF bands. Though one 2 meter J-Pole will work on 70cm quite well so if you only build one antenna build the 2 meter version. I only use the 2 meter version for my 2 meter/70cm dualband handheld. This is a line of sight antenna so the highest practical height you can get it the better. I'm at 20 feet supported by the roof apex on the end of the house. If you house is taller, then any height about 6 to 8 feet above your roof peak would be good. Using the building to support the mast eliminates the need to use guy wires. A cheap mast for light antenna work are 10 foot chain link fence top rails.

What polarization should my antenna be?

Antenna polarization is how the electrical field of the electromagnet wave (RF energy) is in relation to the earth’s surface. If the electrical field is perpendicular to the earth then the polarization is considered vertical. In demonstration, a person walking upright is vertical and a person lying down is horizontal.
In the RF communications world, horizontal polarization is used for long distance and vertical polarization is used for local line of sight communications. Some satellite communications use circular or cross polarization but that’s for a specific use.
Vertical antenna for HF bands can also use vertical polarization because once the beam reflects off the ionosphere it becomes more of a random pattern. More hops equals more randomization.
The biggest factor when communicating direct (no ionosphere) is that the antenna polarizations match. If not the received RF energy will be reduced dramatically.
The venerable di-pole antenna is a horizontally polarized antenna while the sturdy J-Pole is vertically polarized.
To change the polarization of a beam antenna just rotate it so the elements point up/down for vertical or lay flat for horizontal polarization.
If you are using a beam antenna to work a distant repeater the antenna will need to be vertically polarized to match the repeater’s antenna.
If you are working SSB long distance then the beam antenna should be horizontally polarized and so should the distant end.

What should I use to connect my radio to the antenna?

Normally ordinary wire can't be used to connect the radio to an antenna, unless you are using a long wire antenna that leads directly out of the antenna jack on the radio or an antenna tuner. A long wire antenna is simply that, a long wire that is several wave lengths long and not an even multiple of any wavelength you want to listen too. It is a receive antenna but can and has been used successfully as a QRP or low power antenna for CW (or any mode really).
To connect the radio to any other sort of antenna means using either balanced ladder line or coaxial line. Balanced ladder line has been used since the dawn of radio use and is well suited for any balanced antenna like the di-pole. The problem with it is it involves very stringent installation methods and is therefore not easy to work with. It is very low loss but unless you are very familiar with balanced line installation I will discount it as a viable means to connect to the antenna. Most modern radios will only have coaxial PL259 connectors and attaching ladder line will involve a separate piece of equipment to match the ladder line's 450 ohm impedance to the radio's 50 ohm.
Coaxial cable is bar far the easiest to install and connect to your modern radio. It has a 50 ohm impedance so it matches the radio with no additional equipment. If the antenna is also 50 ohms at the desired transmitter frequency then all should work well enough to radiate some signal off the antenna. Coaxial cable is not without some drawbacks that must be discussed otherwise you could be wasting power. Antenna impedance at the desired frequency is very important. The antenna must be cut or trimmed to provide the best possible SWR. In a SHTF situation or a temporary antenna installation a 3:1 SWR might be all that you can manage and it will work but at greatly reduced power. First the impedance mismatch between the radio and antenna will lose power and most solid state rigs will automatically reduce output power if the SWR is 3:1 or greater. Some solid state radios will not even transmit if the SWR is too high. So it's best to try to get an SWR of less than 2:1 even in a temporary antenna installation. For permanent installations SWR readings of less than 1.5:1 are good. Don't spend too much time trying to get the SWR below 1.2:1. In most installations that's about as good as it's going to get. Anything less than 2:1 is going to be OK.
The reason the antenna SWR needs to be as low as possible is that any energy not radiated off the antenna due to impedance mismatch is sent back down the coax to the radio. This is what is called reflected power and that power is sent right back to the transmitter and in severe cases will cause permanent damage to the transmitter. This is why the transmitters automatically reduce output power in a high SWR situation so they don't blow themselves up. If you use an antenna tuner between the radio and the antenna and the antenna mismatch is off the reflected power is absorbed by the tuner and not reflected back to the radio. The antenna tuner does not have delicate solid state final transistor amplifiers to get damaged. The antenna tuner always show 50 ohm impedance to the radio so the radio will never reduce power in a high SWR condition. However the antenna mismatch will still cause power to be reflected back to the tuner so that power is lost. But when using an antenna tuner the antenna reflected loss is not combined with a transmitter reduction loss so the overall loss is less. Antenna tuners are good if you can not for what ever reason obtain a less than 3:1 SWR on the antenna. If your antenna is well matched (less than 3:1) to the transmitter frequency then I'd take out the tuner and connect the radio directly to the antenna as the antenna tuner does rob some of the transmit power.
Another important factor with coax cable is it's efficiency. Coaxial cable is reactive to RF energy and as the frequency goes up the more resistant the coax is to the RF energy. Some cheaper coaxial cables can reduce power as much as 6dB (for VHF frequencies, more for UHF) or 1/2 the transmitted power in 100 feet. So if the coaxial run from the radio to the antenna is about 100ft, not an unrealistic length, then you have lost half your transmitter power. The better coax cable with less impedance to high frequencies costs more but is an investment if you plan to operate on low power. A 100ft piece of 3dB/100ft loss coax compared to a same length piece of 6dB/100ft loss means you can transmit at 5 W for 20hrs/100aH battery compared to 10W for 10hrs for the same effective radiated power (ERP).
So in summary, get the best flexible low loss cable (UV resistant) that you can afford and it will be a good investment toward power savings in the end. Another option would be some super low loss 75ohm TV coax used for digital cable. Even with the impedance mismatch the line loss is so low it makes up for it and the net gain is in the positive. Good low loss TV coax should be readily available in SHTF conditions especially in urban settings. Many Hams use 75 ohm coax connected to a dipole antenna (for HF not VHF+) and it works just fine for what they are using it for.

Radio Communications Systems During Crisis Situations (Power)

2011-09-13T22:35:00.000-07:00

This is part 4 in an ongoing series on radio communications during a crisis event.

How much RF power do I need?

As much as possible, but only use the least amount of power required to complete the communication. There are reasons for both high power and low power.
Low power conserves battery consumption and keeps the range of communications as short as possible when trying to maintain a low profile.
High power is used to reach out longer distances when conditions form weak propagation but propagation is still possible. No amount of power will reach out long distances if the conditions for propagation are not favorable.
During the best propagating conditions one can talk (voice) around the world on 5 watts or less using a gain antenna. Using a low power mode such as CW or PSK31 even milliwatts (less than a watt) is all that is required to communicate long distances.
I know I previously said as much power as possible and sure that would be nice. However it’s not practical to have all that power as the battery or power source requirements would not be feasible in SHTF conditions. 100 watts is the most feasible transmitter power running from a 12 volt system. That’s from a fully charged battery putting out 13.8 volts. To get 200 watts of transmitter power the voltage requirements jump up to 85VAC for the ICOM IC 7700 ($7000 retail, almost 9 times the cost of the FT857D). This radio now requires a generator to operate and dino fuel is scarce and expensive WTSHTF. So how much better will 200 watts sound at the receiving end compared to 100 watts? Only about 25% better because of the inverse square law. However depending on how noisy the conditions are at the time 25% might mean the difference between copying the communication before the transmitter batteries die and not hearing the transmission at all. To use the full legal limit power of 1500 watts you’ll need a full house generator to supply the required power and the expensive power supplies to provide the amplifier the required power. Expensive equipment and expensive fuel consumption! Instead of using transmitter or amplifier power to boost the transmitted signal which costs exponentially more money and consumes exponentially more resource power there is a better way to amplify the RF signal using an antenna. We’ll talk about antennas more later.

What type of power sources should I use?

Unless you have unlimited fuel and will be running generator power throughout the crisis you will need some sort of battery bank to run the radio equipment. If you stick to the radio types recommended here the most power you will require is from a 12 volt deep cycle battery bank for the mobile/base radios to AA or AAA batteries for the portable hand held radios. The 12 volt batteries should be charged via solar or wind power through a charge controller so as not to over-charge and damage the batteries. The AA or AAA batteries should be rechargeable via direct solar charging from the solar panels or 12 volt battery bank and not through wall warts that use converted DC to AC/AC to DC voltage. There is substantial waste converting the DC to AC and then AC back to DC to charge the batteries.
Save wasted power by not using 12 VDC rectified power supplies that run off of 120VAC. Again much needless energy waste happens in the conversion process. Stick to direct battery power where the only losses are in charging the battery and cable resistance loss. Speaking of power cables, they should be heavy enough for the 22A current draw when transmitting at 100 watts of power and I’d even go up a gauge in size to help reduce the power cable loss even more. The min gauge is set for safety reasons but the cable will still be wasting energy which you can feel as the cable warms up. Use the largest feasible wire (cost/ease of workability/available connectors) possible so as to conserve precious battery power.

How long can I expect to operate off one battery charge?

A typical 12 volt lead acid battery is capable of taking a charge from a 14 volt (14.4 typical) bulk charge source before it starts to damage the battery. At 13.4 volts (float charge) the rated output power of a typical mobile/base radio will be close to 100 watts. So while the charging source is applied to the battery your radio will be transmitting at or near 100%. Once the charging source is removed a fully charged battery will output about 12.7 volts. At this level your radio will produce about 92 watts. At 12.4 volts your battery is about 75% capacity and at this point it should be recharged. If not then sulfur will build up on the plates and begin to shorten the life of the battery. At this level your radio will only be outputting about 90 watts. As the battery drains down to 12.2 volts the radio will only put out about 88 watts. At this point the battery is getting to 50% capacity.
A 100Ah battery will run the radio in receive mode (squelch open mode 1A) for about 50 hours before it reaches 50% capacity. However, for longer battery life (longevity) it is recommended not to run the batteries below 75%. So the most you can run off a 100Ah battery in receive mode is about 25 hours or one day. If the radio was to transmit at full power (22A) the time to 75% capacity is now at just over 1 hour. Reducing transmit power to 25 watts will get you about 4 hours of transmit time. 10 watts will get you 10 hours of transmit time. 5 watts of output power consumes about as much power as the radio in receive (squelch open) mode or about one day of operation or 25 hours. I’ve used rounded numbers here for easy understandable math. These are just rounded ball park figures to give you an idea on battery drain compared to output power. Remember 5 watts of power during the best propagation conditions will travel all around the world with the right antenna.

In the next series we'll discuss what antennas to use.

Radio Communications Systems During Crisis Situations (Radios)

2011-09-13T20:56:00.000-07:00

This is part 3 in an ongoing series on radio communications during a crisis event.

What type(s) of radio should I have?

Just like tools certain radio types work better than others in different situations. You should use a hammer to pound nails rather than a shovel. It just works better. Also different hammers work better at certain types of hammering jobs likewise different modes of operation work better in some circumstances than others. You wouldn’t use a sledgehammer to drive a finish nail in a piece of skirting board.

While it would be nice to have one of each radio system available plus spares it just isn’t feasible or cost efficient nor is it necessary in a crisis situation.
Instead of having several radios it would be better to have an all mode/all bands (or at least the popular bands) radio and one spare. That will help keep your comm. gear footprint in check. Older radio systems and some home built systems have a separate transmitter and receiver box. I don’t recommend using the big sets that take up precious space. The reason I don’t recommend them is not only do they increase your comm. footprint, they are not readily portable, and consume more power than a single transmitter/receiver (transceiver) box. When considering a comm. system for emergency crisis situations you’ll want a radio that is small yet puts put decent power (preferably adjustable output power) and one that uses minimal power consumption (especially in receive, squelch, or standby mode). Most modern transceivers made today meet these requirements. Small is better for spare(s) storage and also for hiding your in-use equipment in case of visitors. It’s quite hard to hide in plain sight separate large transmitter and receiver as together they would take up most of the top of the average sized dining table. Also small is better for portability reasons in case you have to bug out. Just unhook the antenna cable(s) and the power wire and shove the small radio in your BOB.

If you can’t afford a new radio system and are forced to look on the used market, try to get an all mode all band radio that at least has 80, 40, 20, and 10 meters. Try for 6 meters and if possible 2 meters VHF also. Having these bands available will cover most if not all your communications requirements. Having 160 meter band is not critical and the problem will be the antenna size. We’ll cover antenna sizes in a later session. Having 6 meters available is also nice but long haul communications may not be possible especially during periods of low solar activity. If I were to skip a band it would be 6 meters since that band is not open for reliable communications all the time. In a crunch you’ll get by with just 40 and 20 meters in the HF bands. You may find small 40 and 20 meter SSB/CW radios that were built from kits. Since these aren’t commercial rigs you can probably get them for a song. Being built from kits you may be able to stock up on some of the major components as spare parts and repair the radios if they ever fail. That's a viable option even if only for a spare radio.
For the VHF bands a 2 meter FM radio will cover most of your local communications needs. If the local repeater is powered by alternate power source (most are) all the better, it will greatly extend the communications range of a low power radio. A UHF radio in the 70cm band is nice to have but not essential. Dual band VHF/UHF radios are abundant but usually cost at least twice as much as a single band radio. These radio packages come in mobile sized packages the size of a CB (or smaller) and hand held walkie-talkie types that range in size from an Altoids mint can to the size of a multi-function TV remote. If I were to only get one VHF radio it would be the 2 meter FM 50 or 75 watt mobile if I was any distance from the local repeater or a smaller handheld in the 5 to 7 watt range if the local repeater is close by. With an external antenna such as a J-Pole (discussed later) handhelds go quite a distance. From my location I can hit the repeater about 80 miles away with the J-Pole at ground level. The repeater is on a high mountain (10,000ft) and in clear sight of my location so don’t expect that range between two radios at ground level. We’ll discuss antenna height in a bit. A 2 meter all-mode would be better but there are none on the new radio market and on the used market they are scarce.
You’re going to need a base station and as many portable radios (not necessarily amateur frequencies though) as you can muster or think you could possibly use. The portable radios are indispensable for anyone working or traveling outside the protected areas. While I recommend personnel travel in pairs (buddy system) it’s not always possible or warranted in certain times but having a means to communicate back to base in the event of an emergency goes a long ways in being prepared.
For local use around the community I highly recommend purchasing Part 15 (no license) devices such as Family Radio Service FRS or CB walkie-talkies. They are cheaper than amateur radio gear and don’t require a license to use. They are usually low power so they are only good for up to a mile or so depending on terrain. Don’t pay attention to the wild claims of 20 plus miles of range. You might get that kind of range if both parties were standing on top of a mountain top with clear line of sight. At ground level with trees and terrain obstacles your range will be much less. Leaves and ground obstacles eat up a lot of RF energy at these frequencies. Also since these radios are to be used for short distance around your block communications, high power (or long range) radios are not required and will use up your batteries faster. Keep the power levels low for this type of use and your battery life will be longer. Remember FRS radios will not work with you Amateur radio so in addition to portable FRS radios you’ll also need a FRS radio for a base station. There are modifications (illegal) that can be done to the radio so you can hook the base radio up to an external antenna. This will extend the range of even the portable radios as the base station now has better ears and a better mouth. Another radio type is General Mobile Radio Service (GMRS). These radios require a license which extends to immediate family members but requires no test. These radios can output up to 50 watts and can have external antennas. They cost more that FRS radios but a base station with a high external antenna on flat ground will reach out 20 plus miles if needed.
For more private/secure communications there are several choices. However remember no radio frequency communications are secure unless some sort of encryption device is used. Use obscure frequencies that are not normally used by the general populous. A marine VHF radio makes a good radio for inland communications so long as you are a fair distance from the coast and any major river transportation routes (Mississippi/Missouri rivers/Great Lakes). Low power handhelds are good options, stay away from the high power radios used onboard ships unless they are capable of reduced power modes. You don’t want your signals to go much further than around your retreat. Commercial fleet radios are another good option for a SHTF radio. These do require an FCC license to operate but when the worst of it is upon us that won’t matter. Most fleet radios have programmed channels and only a few will be programmed. If you can try to get the programming software along with the radios so you can program your own frequencies. The problem with fleet radios is they are higher powered and may not have the ability to reduce power. Some radios, especially portable walkie-talkie types can operate on different voltage levels and this has the added feature of being able to increase or decrease the output power. Check for a radio that has a wide operable voltage range. To reduce the power of a 3 cell AA battery system, just remove one of the batteries and short the space where the battery was with some wire or metal (tinfoil wrapped in tape with the ends uncovered). You have now just reduced transmit power to 2/3 of what full power was and saved a battery in the process. If more power is needed just put the 3^rd battery back in the radio. No physical modifications. These systems are suited for around the retreat or convoy operations where low-power more secure communications are warranted. GMRS radios are also a viable option as they are more expensive than FRS and may not be as popular in the community. They are usually more powerful so make sure the power can be reduced.
For handheld amateur VHF FM radios any model you can get your hands on is a good model; especially the newer ones. Yes some will be better than others but for what you are going to use them for any model is going to do the job. Features to look for on a handheld VHF FM radio are a removable antenna so you can connect an external antenna for better range, one that uses readily available batteries, AA or AAA. Stay away from proprietary battery packs as when they fail, and they will, you will have to rig some alternate power source and possibly damage the radio. A lot of radios may also have a AA or AAA accessory pack that can be used in lieu of the proprietary battery pack, so pick one of those up also. Radios with a standby mode are great on conserving power consumption. In standby mode the radio basically goes to sleep for a second or two, then wakes up and listens to the frequency it’s monitoring and if silent goes back to sleep. This can cut power consumption by 2/3. The radio will not scan frequencies in standby mode so it’s only a viable power saving method if you are monitoring one frequency. Another feature that could be useful is a cross band repeater. This will only be available on some of the higher end dual band radios. Only one of your dual-band (2meter/70cm) hand held/mobile radios needs to have this capability. What this allows is the ability for the radios on 2 meters to communicate with the radios on 70cm. By having one radio with this capability set in repeater mode you have greatly widened your community/neighborhood communications system. This radio will be set as a base radio and can’t be used by a person in this configuration. So make sure if you sacrifice a radio for this purpose you have another you can use for operations.
If you are purchasing new and can spend about $1600 (for just the main radios, primary and spare), the base/mobile radio that I recommend is the YAESU - FT-857D. At about $800 each this radio is small, covers all the HF bands + VHF 6 meters and 2 meters and UHF 70 cm. It is an all-mode radio and has the 3 main modes CW/SSB(LSB-USB)/FM that you will need to communicate. It also has AM and WFM in case you are in contact with a station with only those modes. Current consumption in squelch mode is 550mA (there is no standby mode), 1A in receive (squelch open), and 22A when transmitting at 100W. You may not need 100W for most communications especially low power modes such as CW and PSK31. More on required power and operating modes later. The cost of this radio is about the same cost (or less) than if you bought 3 different radios on the used market to cover HF/VHF/UHF (good deals not withstanding).
The FT-857D is a fairly rugged design and will withstand some moderate abuse in a portable environment. It is not advertized as MIL-SPEC but most reputable manufacturers these days do conform to some electronics construction specifications/standards. I wouldn’t subject the radio to copious amounts of water but a light splashing should not cause any problems especially away from the front panel. If you are going portable with a radio a water proof wrapper/sleeve is a must-have.
There is the FT-857 model that is older and is exactly the same radio except the D model has the Digital Signal Processing (DSP) filter built in. The 857 (non D) model does not have DSP but it can be installed if you buy the module. DSP is not required it just helps filter the signal you are trying to receive better. If you find a deal on an older FT-857 (non D) model don’t hesitate to snatch it up.
Also the FT-897 and 897D (DSP) models are the bigger brothers to the 857. It is virtually the same guts in a different (much larger) package that allows installation of internal power supply (requires 120V AC) or battery pack(s) that operate the radio on reduced power (20W max). It’s receive and transmit power consumption is the same (1A/22A respectively) however the squelched power consumption is 50mA more (600mA) than the 857 model. It costs about $130 more per radio and to me for a SHTF radio it’s not worth the extra cost.
However if the radio is to be used more for hobby/enjoyment in a fixed location (that's why I'm getting this model) and the extra $130 is not a deal breaker, I recommend the 897D due to its larger face panel/display screen and larger knobs. There are more buttons available on the front panel so less menu access is required to change the more common settings. If a good deal can be found on a used model don’t hesitate to snatch it up either.
All four of these models also have a very useful feature called a spectrum scope. This allows one to visually see if a frequency has a signal on it without having to scan the entire band. A quick visual for a few seconds will reveal if anyone is transmitting or not. This is a great feature to quickly scan all the bands for activity and thus reduce power consumption. Most of the older used radios don’t have this feature and is a factor in considering whether to buy new or older used equipment. Some of the more expensive base style radios have a better spectrum scope with more resolution and can even display out to a computer monitor for easy viewing. I’m not sure the added expense in equipment and power consumption is worth it though.
Either one of these four radios will work just fine for the intended purposes and if you can find one on the used market for a few hundred bucks then grab any of them.
Other manufacturers have similar models with similar features however an all-mode/all-band radio in this price range is not available. The closest one is the ICOM IC-7000 at $1240 each retail. The added features and specifications are better but the added cost and a whopping 1.2A (double the 897D) squelched mode power consumption don’t make it the best SHTF radio in my book. The transmit consumption on all the 12V 100W radios is about the same, it’s the squelch and receive consumption that will chew up your battery. A more feature rich radio will cost more and chew up more power in idle mode.
Since this section has a lot of material I’ll summarize here:

What I'm going to have in my kit:

New FT 897D with a used FT 857 or 857D for a spare or mobile rig. Still need to purchase.
Icom 2100H 2 meter FM rig. Purchased 2004. Great solid reliable rig!
Icom W32A 2 meter/70cm dualband portable. Another solid performer with dual band repeater mode. This is my in the house scanner to monitor the local repeaters. Its a true dual band where I can scan both bands at the same time and hear both transmissions. Awesome. It's hooked to my copper J-Pole mounted at 20'.
Older Kenwood TS180 HF 160 - 10 M 100 W. My HF backup backup. It's huge but it's already in the inventory. Great radio that's over 30 years old and still running strong! Don't buy one for SHTF preparedness but any radio you currently own keep or trade for 2 of another type you do need. I'd trade this in a heartbeat for two more 2 meter/70cm 5W+ dualband handhelds of any brand.
Radio Shack 2 meter FM radio that works 50/50. I'll keep for spare or trade during SHTF times.

Radios that you need (minimum):

One HF at least 80 through 10 meters. 40 and 20 meters are a must! 100W output power (the standard for base/mobile amateur radios) and capable of power reduction to at least 5 watts.
One 2 meter VHF FM mobile (50 to 75Watt) with adjustable output power settings.
1 spare for each type (if you can afford it)
Alternate radios that use obscure frequencies (marine bands/fleet radios etc) or low power GMRS radios for more secure personal communications.

Radios that you may want to consider:

HF/UHF/VHF all mode all band transceiver. (base station) Highly recommend the FT 857 or FT 897 (D or non D models) as they contain all you need in one package.
One 2 meter/70cm dualband VHF/UHF FM mobile (50 to 75Watt) with adjustable output power settings. (vehicle/mobile operations)
Portable 2 meter/70cm VHF/UHF FM handheld w/ removable antenna the more watts the better. Adjustable power output even if by removing battery cells. Standard AA or AAA battery packs or accessory packs.
1 Spare of each of the above or combination of different spares to cover all the band segments. Band coverage is more important that same brand spares.
As many FRS and/or mobile/base/walkie talkie CB radios as you can afford for neighborhood/community communications (good barter items also). These can be picked up at yard sales for a few dollars. Keep one base station CB with SSB capabilities for yourself as this can be used for long distance communications with a beam antenna.

Remember it is important to store all unused radios with silica gel desiccant packs in sealed/grounded metal boxes that the radios will fit in. FRS and walkie talkie radios can be stored multiple to a box. Foam padding or bubble wrap will help absorb shock in the event a box is dropped. Do not store batteries in the same boxes as the radios! Make sure all batteries are removed from the radios before they are put in storage!
If you can only buy one radio and have $800 in your budget get the FT-857D!

Stay tuned for the next post in the series in which I will discuss radio power.

Radio Communications Systems During Crisis Situations (Licensing)

2011-09-11T23:40:00.000-07:00

This is part 2 in an ongoing series on radio communications during a crisis event. The introduction can be found here.

Do I need a license?

A license is not needed in the sense you can still communicate without a license. A radio license is not like a software license where the software is restricted without obtaining a license or quits working after the trial period ends. A radio will transmit on whatever frequencies it is designed to transmit on regardless of license. However, depending on the frequencies you want to transmit on and what country you are located in a license may be required by the government. There is a caveat in the United States, FCC rules state during a situation where the threat of loss of life or property exists anyone may transmit on any frequency if no other means of communications are available.

Having said all that I highly recommend getting an Amateur Radio license if for nothing else the little knowledge required to pass the test(s) will be useful in a crisis situation. There are three levels of Amateur Radio class licenses available currently. There are 3 other classes that are no longer available but are grandfathered for those that have those license classes. I’ll not discuss those here. Learning Morse Code is no longer required for any of the available license classes. However not being required does not mean you shouldn’t learn it as Continuous Wave (CW) modulation (the method Morse Code is transmitted with) is very viable in poor propagation conditions and the equipment is simpler/smaller and requires less power to operate. I’ll discuss more on CW later.

Each higher class license gains the legal use of more radio frequency spectrum but requires more advanced knowledge of the required information. The entry level license, Technician, grants all modes on amateur frequencies above 30MHz, CW on portions of some of the amateur HF frequencies, and FM/SSB on portions of the amateur 10 meter band. The next higher class, General, grants privileges on a lot of the HF frequencies (on all the amateur bands) as well as all the privileges of the Technician license. The highest class license, Extra, grants privileges on all the amateur frequencies.

The license class I recommend studying for is the General class license. It grants privileges on most of the frequencies on all the amateur bands. Only a small portion of each band is not legally available to a General class licensee. However remember during a life/property loss situation all that goes out the window anyway. In order to test for the General class license you will also need to pass the Technician license test. All tests can be taken at the same sitting for one testing fee but you must take each one in sequence.

The main reason I recommend getting your amateur radio license is the pool of resources opened to you in the way of other amateur radio enthusiasts, clubs, Amateur Radio Relay League (ARRL) membership (though actually you don’t need to be licensed to be an associate member of the ARRL), actual practical legal use of the radio frequencies and the camaraderie and networking available to you as a duly license Ham. Without a license most of this invaluable resource pool will be unavailable. Hams are cliquish in that respect, but to be in the clique all you need is a valid callsign.

Another good reason to get an amateur license is that obtaining Amateur radio gear will be a lot easier and less expensive. Without a license obtaining a radio will be akin to buying one off the black market. They are available but you will pay more for one. Being a newly licensed operator may get you some free used gear from another licensed Ham or at least decent pricing.

In the end WTSHTF you won’t need a piece of paper to press a button and speak into a microphone to call for assistance.

Why do you recommend I at least obtain a General class license?

A portion of the 10 meter band (28-28.5MHz) is available to the Technician class licensee. During periods of active solar activity the 10 meter band is a viable means of long haul communications on little power. The problem is the peak of the solar cycle comes every 11 years and only lasts 3 to 4 years with a fairly steep ramp up and down. 2 years may be the prime timespan for good communications on 10 meters. That leaves less than 9 years where the band is not the best and during the few years of solar minimum 10 meters is pretty much useless outside of local communications.
In contrast the 20 meter band even during the solar minimum can and does propagate during the day enough for high reliability modes like CW or PSK31 to be considered a viable means of communication. During the last solar minimum which was of a record setting length with nearly twice the number of days with no solar activity (821days) than a normal year (about 480 days) I was able to communicate from my residence in Florida all up the eastern coast and across the great circle route into Europe and eastern Russia. In the reverse direction I was able to communicate to all of the South Americas albeit to a less dense Amateur population. I also communicated with California, Alaska, Hawaii, and even Japan (on SSB voice no less). This was from a simple setup with a radio that was over 30 years old through a simple homemade dipole antenna hung at only 20’ through an oak tree and radiating 50 watts or less. I mainly used a mode called PSK31 which is why I was able to do this on such a modest system. As a Technician I would not be legally allowed to use this band at all. As a General class licensee a majority of this band is available for legal use.

The amount of study is not much more for a General class license than for a Technician class license. If you know the theory behind the questions asked for the Technician license you are well on your way to knowing most of the General license material. The main difference between the tests is knowing the theory rather than memorizing the material. To study for the Extra license class involves yet more theory and advanced mathematics. For the extra privileges gained it may not be worth the extra effort especially if you are pressed for time in your preparation work. However since the entire question pool and answers are available for study, if you can memorize the material you can pass all of the tests and gain all of the privileges. Knowing the theory does go a long way to understanding the questions though.

One of the major reasons many people don’t want to obtain a license is they want to maintain anonymity and since license information is publically available to include mailing address they deem this as a major OPSEC violation. And they are right to think that to some extent I suppose, especially if the mailing address points to where they will be retreating during the crisis. The same can be said for ordering supplies/guns/ammo and shipping them direct to the retreat address. I wouldn’t recommend doing that nor do I recommend putting a secure location on your amateur radio license application. The FCC rules state the address must be located in an area governed by the FCC and you can receive your USPS mail at that address and no mail is returned to the FCC (a license revocation offense). So don’t use your retreat address for a license application just like you wouldn’t use it to deliver goods to. OPSEC adhered to and legally licensed!

Stay tuned for the next post in the series in which I will discuss what types of radios to get.

Radio Communications Systems During Crisis Situations (Intro)

2011-09-11T23:19:00.000-07:00

This series of posts will cover aspects of radio communication in preparation and use during a crisis or WTSHTF or TEOTWAWKI situation. It will be in a Q&A format. Please post questions you want answered in the comment block and I will do my best to include it in the series if it warrants it. If not I will try to answer it in the comments.

So let's get started.

What is a communications system?

A communication system is made up of devices that employ one or two communication methods (wireless or wired), different types of equipment (land-line telephones, intercoms, cell phones, portable radios, mobile radios, base/fixed station radios, repeaters/tin cans & string), and various accessories (examples include speakers, microphones, battery eliminators, and carrying cases) and/or enhancements (encryption, digital communications, security measures, and interoperability/networking) to meet the user needs.

Radio communications are wireless and play an important part in communicating during a crisis if the communication infrastructure or power grids are down. Radio waves do not need a man-made or powered (wired) supporting infrastructure as they travel through the air. Largely depending on the frequency of the radio wave and atmospheric/ground conditions and less importantly on the power used to transmit, radio waves will propagate locally in and around your neighborhood or around the world.

Why are radio communications systems important in a crisis?

When one thinks of being prepared for any given crisis and what logistics are considered important one thinks of food/water, shelter/warmth, and protection/security. And one would be correct; these are the basic needs in any given crisis situation especially in a long term widespread scenario. Often, not much thought goes into how to communicate during or after a crisis before order is restored and even if some thought is given it usually isn’t enough or based on a lack of knowledge. This leads to a communications system that is not up to the job and a waste of money and energy that would be better off put into more food/supplies, better shelter/comfort, or better weapons/security systems.

Depending on the crisis radio communications may or may not be required. If the power grid and commercial communication links are intact then communicating via cell phone/land line/internet might still be available even if limited. However, even if the cell towers are functioning there will be an increase in phone calls being made that will overwhelm the cell phone system and making phone calls will be hit or miss. During 9-11 NYC cell phone system was jammed even though the communications infrastructure wasn’t damaged, at least outside of ground zero. Even in Florida we had problems getting cell phone calls through the system during the initial phase of the crisis. During Hurricane Katrina (in the Biloxi/Gulfport area alone) it is estimated that 2000 cell towers were taken off line (over 20 million calls didn’t get through) and only half of the cell towers were restored within a months’ time. Even land lines were affected and an estimated 22,000 homes were without phone service during the first 30 days after the storm. Do you want to take your chances with your cell phone or land line if your life depended on whether the call goes through or not? [ref: http://www.inderscience.com/search/index.php?action=record&rec_id=33339]

In a widespread crisis that lasts any length of time where travel to and from the crisis area is restricted or impossible there will be a need to communicate with areas outside whether it be personal health and welfare or official government communications. Food, water, medical supplies will be in need but how are you going to dictate how much or where they are needed if the communications infrastructure is down?

How about communication with your neighbors? Instead of running door to door in possible dangerous situations (power lines down, rioting/looting crowds, nuclear/chemical/biological contaminates) you could have a local radio or landline/intercom network to relay messages to a neighbor(s). Building a neighborhood communications network may also help to foster a close(r)-knit community that sticks together during a crisis instead of disbanding into an “each man for himself” mentality. The problem will be convincing your neighbors of the importance of such a network enough for them to act on it. They’ll agree it’s important but think since the chances are so slim that such a crisis will happen that they discard the notion as too much effort with little gain. Just remember when the crisis does happen people will be knocking on your door which leads me to crisis preparedness in general, if you are prepared to handle a crisis and are prepared to help others then you are part of the solution rather than part of the problem. Being prepared puts less stress on the community and the more people who are prepared the better off the community will be to handle the crisis.

Stay tuned for the next post in the series where I discuss licensing.

Perseid Meteor Shower This Weekend

2011-08-10T08:58:00.000-07:00

Meteor Scatter!

More info here.

Rental Property

2011-07-05T07:09:00.000-07:00

We'll we're in a rental property as of April but only have a 2 meter J Pole set up at the moment. Not sure if I'm going to put up the OCF or not or wait until we purchase some property.

I have Echolink up in scanner mode currently as I need to make a PTT interface for the HT that I will be using as the Echolink radio. It's scanning the local repeaters to include the EAARS repeater network that covers the whole SE of the state. Pretty neat network.

In Limbo

2011-03-22T08:14:00.000-07:00

We've since moved from our QTH in Florida and are in limbo status at a relatives house until we get a place of our own.

Hopefully will be back on the air April/May time frame but until then you may find me on Echolink if I'm online.