GW6PFK

rtl sdr what a big world of radio.

noreply@blogger.com (Unknown) — Mon, 01 Dec 2014 18:00:00 +0000

got one of these on e-bay and found it a bit tricky at first. usual thing most software for fun stuff is on Linux and window won't let you compile it even if you have all the listed dependencies?
then I found window binaries for http://sdr.osmocom.org/trac/wiki/rtl-sdr.
Linux was very easy follow the instruction. Gnuradio as yet I can get to work on window and was tricky even on Linux my tip is if you have any problems install GQRX and it seems to fix any problem? and it is not a bad GUI.

if you are looking for example at http://sdr.osmocom.org/trac/wiki/rtl-sdr the link to https://www.cgran.org don't work.

also be warned this is all processor intensive my Windows 8 laptop is a beast quadcore 64bit but getting software to run is a pain and my Linux machine is single core + 7 years. but you can install and run loads :(

Cool stuff
http://www.rtl-sdr.com/

www.eb3frn.net

http://hackaday.com/2012/06/17/ask-hackaday-has-anyone-built-a-radio-telescope/

An extra note on newer Linux watch out for driver problems. you may need to blacklist the TV driver. see post http://www.kubonweb.de/?tag=rtl-sdr.
this is for a PI but get the idea.
look in /etc/modprobe.d/
and these are the drives:
blacklist dvb_usb_rtl28xxu
blacklist rtl_2832
blacklist rtl_2830
also see this if on Ubuntu, http://m0dcm.co.uk/?p=423

"Open a Terminal and type

sudo gedit /etc/modprobe.d/no-rtl.conf
Once you’ve entered your password and the text editor has opened, copy and paste these few lines into it

blacklist dvb_usb_rtl28xxu
blacklist rtl2832
blacklist rtl2830
Now press save and reboot the PC"

needed above Ubuntu 11.
next time I'll explain if you get jumpy audio but off to play now.

did anyone see anything?

noreply@blogger.com (Unknown) — Sun, 12 Jan 2014 13:32:00 +0000

http://www.gi.alaska.edu/AuroraForecast/Europe/2014/01/10

that was a 5, it goes up to 9 would you see it in London?

Iss heard! 145.825Mhz 3/8/13 13:20 local time APRS

noreply@blogger.com (Unknown) — Wed, 04 Sep 2013 12:26:00 +0000

PIC-et radio?

noreply@blogger.com (Unknown) — Mon, 07 Jan 2013 19:30:00 +0000

www.webalice.it/capaso/DOCS/APRS/dcc.pdf

found the above link and with the python code I found I'm sure I could write a C program to generate APRS packets.

As a start make a wav file and play it on a PC.

I'm well versed in writting code for gcc/mingw compilers, could set up a google code site.

and then transfer to a micro?

As it don't look over complicated,

APRS on android almost?

noreply@blogger.com (Unknown) — Sun, 06 Jan 2013 19:30:00 +0000

I found this http://technofart.blogspot.com/search/label/aprs.
An APRS generator written entiarly in python, YEPPY.
hold on PL4A does not have pyaudio or numpy :0(
but it does have wave, I wonder if I could convert the code to generate a wav file and then send it.
wonder if any one has done simulare in C for Mingw on PC.

PL4A has access to GPS so it could auto update position.

FITSAT morse in the sky

noreply@blogger.com (Unknown) — Fri, 07 Dec 2012 14:30:00 +0000

http://www.fit.ac.jp/~tanaka/fitsat.shtml posted this on twitter. the morse bit is cool but it has an onboard camera with shots like these.

being transmitted on a 5.84GHz link real satelite TV

Blogway test

noreply@blogger.com (Unknown) — Sat, 10 Nov 2012 08:29:00 +0000

Seen this android app and giving a go.

Slow to type on a phone but ok for quick posts

CB or not CB

noreply@blogger.com (Unknown) — Thu, 18 Oct 2012 06:30:00 +0000

I've dugg out my old scanner ( bought to moitor bands I didn't have rigs for) and was looking up the current state of play in UK of what you can and can't listen to it comes down to

Broadcast
Ham Radio
CB (big change from the old days
and an odd one navigationl broadcasts?

dose PMR446 come under CB?
and is there anything on CB 27Mhz as from investigation look like it's 80channel ( old UK 40 + EU 40)?
no licence great but set up scanner with best I can UK 40 is an odd offset.
not a sausage!
got some distant under the squelch on 10FM nothing I could make out. SSB-10M was better.
CB nothing.
if anyone is using CB let me know, it would be nice after all though people protested to get it in the 70s and 80s.
is PMR446 the new CB?
and can you listen to it to find out?

Little people invading?

noreply@blogger.com (Unknown) — Wed, 15 Aug 2012 18:30:00 +0000

Little people invading?

Seen a lot of radio stuff with 433Mhz written on it recently. I have a clock with temperature display and a remote transducer with the said mark. So I got my uv-3r out and had a scan around and found it’s burp on 433.920Mhz but if I go up 5khz and open squelch I get an almost constant stream of chirps and burps. Further investigation found http://en.wikipedia.org/wiki/LPD433 , http://en.wikipedia.org/wiki/Low-power_communication_device and http://en.wikipedia.org/wiki/Remote_keyless_system. Low and behold my car keys give out a buzz near there.

As well as that we have http://ukhas.org.uk/general:beginners_guide_to_high_altitude_ballooning doing some cool stuff on 434.075Mhz, http://ukhas.org.uk/guides:tracking_guide. They have their own protocol http://ukhas.org.uk/communication:protocol looks simpler than APRS and works ok, this is the sort of thing we could all be doing if not for http://licensing.ofcom.org.uk/binaries/spectrum/amateur-radio/guidance-for-licensees/samplelicence07.pdf section 9(3)

9(3) Without prejudice to Clause 1 of this Licence, the Licensee shall not establish or use the Radio Equipment in any Aircraft or other Airborne Vehicle.

We could make use of this simpler protocol on HF? For direction finding as that is the only way we can beacon other than 144.800Mhz without NOV (notice of variation)

I also noticed we were turfed out of parts of 70cm for the Olympics. 70cm is a nice big band in a prime part of the spectrum and we have it on a secondary basis, if we don’t use it others have the right to do so.

If you a Foundation Licence see table A in the licence, it’s your highest and biggest apart from 10Ghz. So cherish it.

Balloons in uk?

noreply@blogger.com (Unknown) — Fri, 03 Aug 2012 12:30:00 +0000

http://ukhas.org.uk/
they are using a FSK signal on licence free 434.075Mhz in 70cm Amateur radio band, but you can't put an Amateur transmitter in one. not sure why we are limited in this way?

could you hang a becone or video transmitter under a tethered baloon or kite as http://ukhas.org.uk/communication:licence_exempt states

Video: 2.400 – 2.4835 GHz 10 mW EIRP (Effective Isotropic Radiated Power) 20 MHz Bandwidth

can be used?

lots of cool stuff and you can view live on google maps at http://spacenear.us/tracker/

PCB-guide

noreply@blogger.com (Unknown) — Thu, 19 Jul 2012 14:48:00 +0000

I design PCB's for a living but I still like to learn, check out this site-
http://www.frontdoor.biz/HowToPCB/HowToPCB.html
as people always ask how you start.
15years in electronics in my case.

Where should I get on……?

noreply@blogger.com (Unknown) — Thu, 12 Jul 2012 03:30:00 +0000

This is a big question for Radio Ham’s looking at a new band or home. Being new to HF TX short wave listening I’m an old hand at but that was at a different QTH. I looked on the web to help me with this question. I discovered http://www.voacap.com/coverage.html , I think was written originally as a tool for VOA (Voice Of America) a broadcast station. But this online tool can give you some idea of your HF coverage although the map is a little small. Give it a go it’s free.

Going for a more detailed option there is http://www.cplus.org/rmw/rmonline.html an online version of the radio mobile package by ve2dbe see here http://www.cplus.org/rmw/english1.html . For the online version you will need a login and a good read of the documentation but it can give you an idea of good portable sites and links to your best buddy at the radio club.

Got a screen shot of the 2M range from my favourite site Billy in Llantrisant.

so I missed the date

noreply@blogger.com (Unknown) — Thu, 28 Jun 2012 06:00:00 +0000

it was in 2011 but amazing any way!

http://www.trackuino.org/

noreply@blogger.com (Unknown) — Wed, 27 Jun 2012 09:00:00 +0000

http://www.trackuino.org/
had to post when I found and you can follow real time on the map.
http://aprs.fi/?call=K6RPT-11
a balloon on a mission.
build your own from http://code.google.com/p/trackuino/

UV-3R trick!

noreply@blogger.com (Unknown) — Thu, 07 Jun 2012 18:30:00 +0000

If you want to use it as a scanner and are worried you may touch the TX button on a frequency you are not licenced for. The trick is to set the repeater shift to 39.99Mhz on vhf or 69.99Mhz on uhf and the software will stop you transmitting outside the band.( 136-174 MHz and 400-470 MHz)

Also the volume button opens the squelch if you hold it down. Seen this one here http://www.uv3r.com/images/UV_3R_CheatSheet.pdf

they sell them at http://www.uv3r.com/Index.html not where I got mine, so can’t vouch for them.

seen some very brightly coloured ones on e-bay as well.
by the way I set this up on the VFO's for UHF and VHF and got in a real knot when I had to QSY from my stored repeater channel.

pipes callcq map

noreply@blogger.com (Unknown) — Tue, 29 May 2012 19:00:00 +0000

http://pipes.yahoo.com/pipes/pipe.run?_id=8f305e9fb12845891d03f3cf366454e2
some reason it gives me an odd loaction?

spot of DIY

noreply@blogger.com (Unknown) — Thu, 24 May 2012 19:00:00 +0000

one of those things we all need now and again.
http://vk5ajl.com/projects/SWRMeter.php
knowing the principals full well from my days in a radio job, so I had a go.
work you know but with one error swap names of FWR and REV meeasure port.
to this:

With matched terminations on the output ports,

1. A portion of the wave traveling from port 1 (input) to port 4 (output) is

coupled to port 3 (forward coupled), but not to port 2.

2. A portion of the reflected wave traveling from port 4 to port 1 is coupled

to port 2, but not port 3.

3. A portion of the wave incident on port 2 to port 3 is coupled to port 4, but

not port 1; and a portion of the wave incident on port 3 is coupled to port 1, but not

port 4.

thought I had a total miss-match with 50R load but did a few tests and googleing and got it right.

The reflected voltage is r times the incident voltage. Since power is proportional to the square of the voltage, the reflected power, Prefl is (5/7)2 x 4 W = 2.04 W

and the power to the antenna = 4 W - Prefl = 1.96 W

when I work out how to add gerber plot files I will

and a picture of my work.

noreply@blogger.com (Unknown) — Wed, 09 May 2012 18:41:00 +0000

how to get your own QrCode badge.
use http://imagecharteditor.appspot.com/ and copy paste away
and

Bob's your aunties cat??
works with Zebra apps J2ME
see more at https://developers.google.com/chart/image/docs/making_charts
graphs charts so on.

twitter call cq

noreply@blogger.com (Unknown) — Fri, 04 May 2012 12:30:00 +0000

a bit of code I've run up baseed on twitter search api. If you put #callcq tag in your post it will show up here by javascript magic. working on a map if you add geo coding data postcode, gps, QTH etc....
got the idea from http://www.twitwx.co.uk/.

I've stuck my first example on extra page on this site. but this is the main working. it wont run in a post.

<div id="results">
</div>
<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.3.2/jquery.min.js" type="text/javascript"></script>
<script type="text/javascript">
$(document).ready(function(){
var url='http://search.twitter.com/search.json?callback=?&q=';
var query='%23callcq';;
  $.getJSON(url+query,function(json){
   $.each(json.results,function(i,tweet){
      $("#results").append('<p><img src="'+tweet.profile_image_url+'" widt="48" height="48" />'+tweet.text+'</p>');
   });
  });

});
</script>

it's the spots

noreply@blogger.com (Unknown) — Wed, 02 May 2012 18:03:00 +0000

acrding to this http://hamwaves.com/propagation/
more spots higher the band you can use?

forcasting http://hamwaves.com/propagation/forecast.html

stil no muf(Mhz) = SUNspot*K

Gadget wigets continued

noreply@blogger.com (Unknown) — Tue, 01 May 2012 18:05:00 +0000

Why are not all Gadget widgets the same of HF predictions?

and

http://rigreference.com/solar

don't always show same traffic lights colors.
badge one has an explanation at http://www.hamqsl.com/solar2.html
that I'm trying to understand. but does not have any explanation I can find.
I'm going to compare them to what I hear on my trusty Sony portable and let you know which is more accurate.

CQ MAP?

noreply@blogger.com (Unknown) — Tue, 01 May 2012 06:30:00 +0000

Any one know how I could write a Gadgets, widgets or javascript to search twitter for #callingCQ and show anyones tweets with this tag. eventualy it could go on a map like http://uksnowmap.com/ or http://www.twitwx.co.uk/ had a look at their code but not sure about it can't get to bottom of it.

I suppose I could e-mail them?

HF-DATA BADGES

noreply@blogger.com (Unknown) — Fri, 27 Apr 2012 18:14:00 +0000

I'm collecting together a pile of radio data widgets/gadgets on my site. http://sites.google.com/site/gw6pfk/HF-data

see example, I'm also working on gadget wrapper for some of the more awkward ones to go on google sits.
I you see any I may be interested in drop me a line.

The UV-3R is a very interesting beasty.

noreply@blogger.com (Unknown) — Wed, 11 Apr 2012 18:44:00 +0000

The UV-3R is a very interesting beasty. Can cover 136-174Mhz and 400-470Mhz, up to 99 set channels and a vast array of tone and repeater option. weighing in at 130g and fitting in the smallest pocket, cool ha!

See I like it and take it everywhere with me but why is the user interface designed by a mad man? Here are a few examples:

1/ You have to press a very sticky button to adjust volume or switch it off with a loud beep if you need it quiet.

2/ Setting up a memory channel is so difficult that you could not work it out without the manual which is a little obscure itself. There is a yahoo group that is and exalt help.

3/ Once you have your 99 memories set you have to remember what they are. 2M I know well so not to bad but 70cm has got me confused on a number of occasions. Not really the rigs fault all together the band plan is a bit odd any way. A name label would be good.

4/ Scanning needs two key presses and it’s all memories or the whole band UHF/VHF.

5/ Antenna you need to swap it for each band and a nice screw fitting.

The last is more of a hardware problem along with the head phone connector that sends it into transmit if you put normal headphones in. it also locks it transmit if you use the one supplied, see ferrite mod on my picture.

With this taken it’s pretty good for its price range does two bands and gives good reports on the air.

Anyone think they’ll do D-star or a 6M rig??

something you should read if you're into Antennas

noreply@blogger.com (Unknown) — Tue, 10 Apr 2012 15:18:00 +0000

http://www.strobbe.eu/on7yd/136ant/
it's about LF but very enlightening about all antenna design.
such as loading coils and their calculation
A good read in my book