Radio Briker

PIC-based voice recorder

noreply@blogger.com (dB) — Sun, 09 Oct 2011 15:16:00 +0000

[Vinod] just finished building a voice recorder and it turned out even better than he thought it would. The video after the break shows him recording what is surely one of your favorite songs from his cellphone and then playing it back. The audio quality does sound quite good for a project with very few components.

A PIC 16F877A makes up the majority of the build. Its ADC is used to capture the incoming line from an amplified microphone input (you’ll find that amp schematic half way through his post). He’s storing the data on an MMC card, which was a bit of a hack since the PIC has limited RAM to manage that overhead. The stored data is in a raw format, as the card is not accessed using a file system. This makes it easy to record at a high bit rate, leading to better audio quality. Playback consists of connecting a speaker via a low-pass filter and amplifier circuit to the hardware PWM output on the PIC.

Filed under: digital audio hacks

Video – Eagle CAD’s CAM processor

noreply@blogger.com (dB) — Sun, 09 Oct 2011 14:54:00 +0000

Video – Eagle CAD’s CAM processor:

Here is the next installment in our series of Eagle CAD videos. In this video we skip ahead a bit and show off the CAM processor that you use to create the files necessary to have your circuit boards be manufactured. After watching this video, you will know how create a new CAM program, load a circuit board into the CAM processor, tell it where to save your files, and actually use it to create the files.

We’re skipping ahead today because of a screw up on our part. We meant to show the layout portion of the program today but edited the wrong video… We’ll show layout next week. After that, we will show the completed circuit board and solder the parts onto it.

If you are itching for some Eagle CAD layout info, you may be interested in some supplementary videos that we have uploaded to our Youtube channel. In those videos, we show how to use the most important features in the layout portion of the Eagle CAD.

Have you missed the previous videos? Here are some links to them:

Schematic and the beginning of a custom part: [click here]

More custom part stuff: [click here]

Video is after the break:

Filed under: news, video hacks

Video: Eagle CAD Layout

noreply@blogger.com (dB) — Sun, 09 Oct 2011 14:39:00 +0000

Video: Eagle CAD Layout:

This week’s video is the last in a series of videos where we show how to use Eagle CAD. Today we will look a the Layout portion of the program and will create a circuit board from the schematic that we created previously. We start by creating a layout file and then moving all of the parts to appropriate places on the circuit board. After that, [Jack] shows how to route the traces. Along the way, he talks about the tools that he is using and various ways to use them. The end result is a prototyping board for the PIC18F44J11.

Like the others, this video is fairly long at 29 minutes, so make sure to have some time dedicated towards watching it if you do.

In next week’s video, we will be showing this board as it arrived to us from a manufacturer and will do a tutorial on how to solder.

If you have missed our previous videos, you can find them here:

Schematic part I

Schematic and Custom part creation

CAM Processor

We have also created many supplemental videos explaining how to use many of the tools in the tool palettes. You can find them on our Youtube channel:

Check out the video after the break!

Filed under: news, video hacks

RF sniffing on-the-go

noreply@blogger.com (dB) — Sun, 09 Oct 2011 13:57:00 +0000

RF sniffing on-the-go:

It’s been a while since we checked in on [Travis Goodspeed]. His latest post makes RF sniffing with the Next HOPE badge more portable by ditching the need to display data on a computer. He’s built on the work he did at the beginning of the year, replacing the FTDI chip on the badge with a Bluetooth module. Now he can use his Nokia N900 as a GoodFET terminal to not only display the packets pulled from the air, but the control the badge as well.

Previously, the client running on the computer was communicating with the badge via a serial connection. To get it working on the N900 [Travis] transitioned from using py-serial over to using py-bluez. All of the code changes are available from the GoodFET repository.

He’s got a few other tricks planned for this concept. He put in a parts order to add Bluetooth to the Girltech IM-ME. The pretty pink pager has the same radio chip on board, so adding Bluetooth connectivity will allow it to be used in the same way. There are also plans in the works to add a couple other packet sniffing protocols to the bag of tricks, including ZigBee.

Filed under: security hacks, wireless hacks

A laser cutter challenge

noreply@blogger.com (dB) — Wed, 14 Sep 2011 21:35:00 +0000

A laser cutter challenge:

When the Louisville hackerspace LVL1 was discussing the purchase of a new laser cutter, a member said, “I could build one before you get around to buying one.” The gauntlet was thrown down, a challenge was set, and the race was on to build a tiny laser cutter before the hackerspace took delivery of their new laser cutter.

The mechanical aspect of the build is fairly simple. The X axis is simply a stepper motor, threaded rod and laser module mounted on a carriage. This carriage moves along the Y axis with the help of two stepper motors for either side. Everything was mounted on more perfboard than reason would suggest.

For the electronics of the project, three motor drivers were made with a few logic chips and the laser firing relay was stolen from test equipment developed for LVL1′s trans-Atlantic balloon build. Motor and laser control was handled by an Arduino to keep the build simple because the contest was over after the first laser was finished cutting a square.

LVL1 is now working on a second version of the winner of the laser cutter challenge. They’re planning on a touchscreen interface that will cut a plastic blank about the size of a credit card. We can’t wait to see the results of that build.

Filed under: arduino hacks, cnc hacks, laser hacks

ARRL Facebook Page: 20,000 Fans Strong

noreply@blogger.com (dB) — Wed, 14 Sep 2011 21:31:00 +0000

ARRL Facebook Page: 20,000 Fans Strong:

With more than 20,000 fans on Facebook, the ARRL Facebook page is the number one spot for hams on the Internet’s most popular social networking site. Not only is the ARRL page the most popular Amateur Radio page on Facebook, it is attracting many young -- and not-so-young -- hams to share their opinions and ham radio-related news with other hams.

According to Facebook demographics, more than 46...

Beginner Concepts: MOSFETs

noreply@blogger.com (dB) — Fri, 09 Sep 2011 20:52:00 +0000

Beginner Concepts: MOSFETs:

[Moser's] introductory guide to MOSFETs serves as a quick introduction for those unfamiliar with the parts. They fill a similar role as a bipolar junction transistor like the 2N2222, making it possible to switch large loads. But fundamentally they are different. Metal Oxide Field Effect Transistors have three pins for Drain, Source, and Gate instead of the Collector, Emitter, and Base that you may be used to. The Gate is the control pin for the device and offers a desirable advantage over bipolar junction transistors in that it is insulated from the channel. This means that much less current flows into the Gate when compared to the Base of a common transistor, saving power and providing protection to the logic circuitry.

Don’t fret if this makes your head spin. [Moser's] writeup is short and to-the-point but it’s not watered down. You can get a basic overview and if you care to learn more, he’s linked to datasheets and has basic terminology that is easily clarified with a Google search. One of the most powerful tools that he’s included is the simple MOSFET and driver circuit diagram you see above. This makes it possible to switch incredibly large loads very quickly; the true power of the MOSFET.

Filed under: misc hacks

Spectrum analyzer users custom characters on an HD44780 display

noreply@blogger.com (dB) — Fri, 09 Sep 2011 20:50:00 +0000

Spectrum analyzer users custom characters on an HD44780 display:

[Camilo] built a spectrum analyzer to use with his audio system (translate). The hardware is quite simple, using an op-amp, microcontroller and LCD display. He chose an LMV324M low-voltage op-amp which connects to the incoming audio signal and feeds its output to the microcontroller’s ADC. In this case, he chose a Freescale microcontroller from the HCS08 family which is running at 20 MHz. This gives the project enough speed to properly analyze the incoming audio. He mentions that he’s following the guidelines set forth in the Nyquist-Shannon sampling theorem and using the Fast Fourier Transform when processing the samples.

This isn’t the first time we’ve seen a character LCD used as a display for a frequency analyzer. This other ATmega8-based rendition supported several different screen layouts. These displays have enough RAM to store eight custom characters. Each character is 5×8 pixels, lending eight levels to each character for a total of 16 for each column seen above. We love the simplicity of the hardware in the project but we wouldn’t mind seeing an additional potentiometer to fine-tune how the data is displayed on the screen to take advantage of its full range. See the project in action in the clip after the break.

Filed under: digital audio hacks

TSC230 Color Light-to-Frequency Module

noreply@blogger.com (dB) — Fri, 09 Sep 2011 20:50:00 +0000

TSC230 Color Light-to-Frequency Module:

ElecFreaks is selling a new color sensing module based on the TSC230 sensor. They’ve posted a demonstration using an Arduino that shows off what this sensor is capable of. The module includes four white LEDs which give a baseline of light to help normalize readings when reflected off of differently colored surfaces. The white balance of the sensor needs to calibrated in software in order to ensure accurate readings, but once that’s done you’ll be cable to pull RGB values off of whatever you put in front of the sensor.

What a nice addition to sorting machines like this LEGO sorter. Of course you can do something like this yourself using an RGB LED as a detector, but the TSC230 is extremely sensitive and should be quite reliable in comparison. They’re selling the module for $15, a price point that’s hard to beat if you need precise color detection in your next project. A colored token reader for your MAME cabinet perhaps?

Filed under: parts

Laser etched PCB production

noreply@blogger.com (dB) — Fri, 09 Sep 2011 20:49:00 +0000

Laser etched PCB production:

Like most of us, [reonarudo] isn’t satisfied with the current methods of homebrew PCBs, so he put a laser on a reprap and started burning some boards.

The basic procedure is to cover a copper clad board with matte black spray paint. A laser was installed on the X carriage of the reprap. [reonarudo] used cad.py to convert the board files into g-code and fired up his laser. The quality of the boards is highly dependent on the accuracy of the laser so after working through some mechanical problems [reonarudo] managed to make some passable boards.

We’ve seen just about every manufacturing method imaginable applied to PCB production. Etch resist and toner transfer do the job and a reprap milling machine is pretty neat, but lasers are so much cooler. While it may not be perfect (yet), printing PCBs with a laser shows a lot of potential. Check out a video of [reonarudo]‘s bot burning some copper after the break.

Filed under: hardware, laser hacks

Program an Arduino using your sound card

noreply@blogger.com (dB) — Fri, 09 Sep 2011 20:48:00 +0000

Program an Arduino using your sound card:

[Chris] wrote us to share a neat technique he has been using to program the Arduinos he uses in his projects. He likes to build bare bones Arduino clones rather than sacrifice full dev boards, and instead of programming them via traditional means, he is using his computer’s sound card.

He builds a simple dead bug Arduino (which he calls an Audioino) using a handful of resistors, a pair of caps, an LED, a reset switch, and most importantly – an audio jack. After burning a special audio bootloader to the chip, he can connect the Arduino directly into his computer’s speaker port for programming.

Once the microcontroller is connected to his computer, he runs the IDE-generated hex file through a Java app he created, which converts the data into a WAV file. With the Arduino put into programming mode, he simply plays the WAV file with an audio player, and the code is uploaded.

He says that this method of programming comes in handy in certain cases where he builds things for friends, because they can easily update the software on their own without a lot of fuss.

Filed under: arduino hacks, digital audio hacks

Making oscilloscopes from ARM development boards

noreply@blogger.com (dB) — Sun, 28 Aug 2011 20:34:00 +0000

Making oscilloscopes from ARM development boards:

If you’ve got an ARM development board gathering dust in the corner of your shop, perhaps you could repurpose it as an oscilloscope. [Arend-Paul Spijkerman] was able to use an mbed and LPCXpresso as the hardware end of an oscilloscope. He didn’t use a standalone screen as a display, instead opting to push the scope readings from the hardware to a computer for display. This was greatly simplified by using StampDock as a basis for the GUI.

His circuit diagrams calls for an RS-232 connection for the LPCXpresso but not for the mbed. We’re not quite familiar enough with the mbed to know why, but perhaps those in the know can clue us in by leaving a comment. The probe connections are quite simple, each made up of a voltage divider and a pair of diodes. But the breadboard above looks much busier because it has two oscilloscope circuits built on it, and there’s a 10 MHz clock and a 4040 ripple counter which were used to provide a test signal.

Filed under: Microcontrollers

[Dino] tells us about transistor-based on/off switches

noreply@blogger.com (dB) — Tue, 23 Aug 2011 18:48:00 +0000

[Dino] tells us about transistor-based on/off switches:

You know them, you love them, you take them for granted – they are single push button on/off switches. As [Dino] explains in the most recent episode of his Hack a Week series, they are typically implemented in the form of IC logic switches nowadays, but it wasn’t always that way. When they first came on to the scene in the 70’s, the single button soft switches were built using a set of transistors and a capacitor to get the job done, so [Dino] decided to research push on/push off transistor switches a bit and build his own.

After reading through a short tutorial, he was ready to go. As he explains in the video, the operation of the switch is fairly simple, though he did run into some odd issues when he prototyped the switch on a piece of breadboard. He’s looking for someone to explain why the unstable circuit suddenly performs better with the addition of a small capacitor between the battery’s positive lead and the circuit’s output, so if you have some insight, be sure to speak up in the comments.

In the meantime, check out [Dino’s] exploration of push on/push off switches below.

Filed under: misc hacks

DXCC Country/Entity Report

noreply@blogger.com (dB) — Tue, 23 Aug 2011 18:45:00 +0000

According to the Amateur Radio Cluster Network for the week of Sunday, 14th-August, through Sunday, 21st-August there were 212 countries active.

Countries available:

3A, 3B8, 3D2, 3V, 3W, 4J, 4L, 4O, 4S, 4X, 5B, 5H, 5N, 5R, 5T, 5V, 5Z, 6W, 6Y, 7P, 7Q, 7X, 8P, 8R, 9A, 9G, 9H, 9J, 9K, 9M2, 9M6, 9N, 9Q, 9V, 9Y,

A2, A3, A4, A6, A7, A9, AP, BV, BY, C3, C6, CE, CE9, CM, CN, CP, CT, CT3, CU, CX, D2, D6, DL, DU, E5/s, E7, EA, EA6, EA8, EA9, EI, EK, EL, EP, ER, ES, ET, EU, EX, EY, EZ, F, FG, FJ, FK, FM, FO, FP, FR, FS, FY, G, GD, GI, GJ, GM, GU, GW, HA, HB, HB0, HC,
HH, HI, HK, HL, HP, HR, HS, HV, HZ, I, IS, J2, J6, J7, J8, JA, JD/o, JT, JW, JY,

K, KG4, KH0, KH2, KH6, KL, KP2, KP4, LA, LU, LX, LY, LZ, OA, OD, OE, OH, OH0, OJ0, OK, OM, ON, OX, OY, OZ, P2, P4, PA, PJ2, PJ4, PJ7, PY, PZ, R1FJ, S5, SM, SP, ST, SU, SV, SV5, SV9, T32, T7, T8, TA, TF, TG, TI, TK, TL, TR, TT, TU, TY, UA, UA2, UA9, UK, UN, UR,

V2, V3, V4, V5, V8, VE, VK, VK0M, VP8, VP9, VR, VU, XE, XU, XX9, YA, YB, YI, YL, YN, YO, YS, YU, YV, Z2, Z3, ZA, ZB, ZC4, ZD7, ZF, ZL, ZP, ZS

* PLEASE NOTE: The report "could" contain "Pirate/SLIM" operations or
more likely a "BUSTED CALLSIGN". As always, you never know - "Work First Worry Later" (WFWL).

Timor-Leste DXpedition

noreply@blogger.com (dB) — Tue, 23 Aug 2011 18:41:00 +0000

The 4W6A DXpedition is now less than one month away.
Low-band operators will be pleased to hear that the team now has a Titanex V160E 87ft / 26.5m-high vertical antenna for use on 160m at 4W6A.

The antenna was shipped from the manufacturers in Germany and has arrived in Darwin, Australia, from where it will be trans-shipped to Dili, Timor-Leste, later this month.

The team had previously planned to use an 18m Spiderbeam pole as the support for a 160m inverted-L. With the arrival of the Titanex vertical, the 18m Spiderbeam pole will now be used for a full-size 80m quarter-wave folded monopole vertical instead.

Other antennas include monoband quarter-wave verticals for 40, 30 and 17m kindly sponsored by Tony Burt, VK3TZ, of Rippletech Electronics in Australia, a 2-element phased array for 40m, an Australian-made Com-an-tena vertical for 10, 15 and 20m, a Butternut HF6V, a 15m vertical dipole, and a G3TXQ Hexbeam made by team member Ant David, MW0JZE. All the antennas will be located on the beach within a few metres of the ocean.

Thanks to the generous sponsorship received from many DX foundations, clubs and individual DXers, it has become possible to ship much of the heavier equipment to Dili, Timor-Leste, in advance of the expedition. The team is very grateful to all DX groups, companies and individuals that have sponsored the expedition. All are listed with thanks on the 4W6A website atwww.4w6a.com/sponsors

4W6A will be QRV from Atauro Island (IOTA OC-232), Timor-Leste (East Timor), from 16 to 26 September 2011. Activity will be on all bands 10 to 160 metres, using CW, SSB and RTTY with up to four stations simultaneously. The QSL manager is M0URX, direct (SAE plus 1 IRC / $2), via the bureau, or LoTW. The entire log will be uploaded to LoTW as quickly as possible after the end of the operation or, if possible, also during the DXpedition.

Direct or bureau QSLs may also be requested using the M0URX Online QSL Request Service (OQRS) at http://m0urx.com/oqrs(there is also a link from the 4W6A website at
www.4w6a.com/qsl-information).

73,

Steve, 9M6DXX
4W6A Team Member

Eperiment sambil ngetrack ?

noreply@blogger.com (dB) — Mon, 22 Aug 2011 20:09:00 +0000

Kegiatan rekan-rekan Orari makassar di bulan Puasa ini, khususnya yang hobby melakukan uji coba peralatan komunikasi; Antena, Radio dan RF Power Amp. masih tetap eksis pada malam hari di 144.200 Mhz.

Kegiatan uji coba sambil hunting stasiun radio yang berada jauh dari kota makassar, bahkan beberapa hari terahir kondisi komunkasi jarak jauhpun sudah dapat dilalukan seperti dari kalimantan, jawa timur dan bali. Ada fenomena baru dikalangan amatir radio yang aktif di band 2 meter saat ini, biasanya setelah melakukan report dan tukar informasi data stasiun masing-masing dilanjutkan dengan uji kekuatan stasiun "Ngetrack" sambil menantikan waktu sahur....

Ngetrack ... sudah legal?

Build Your Own Class AB Audio Amplifier

noreply@blogger.com (dB) — Wed, 17 Aug 2011 18:47:00 +0000

Build Your Own Class AB Audio Amplifier:

[Dino Segovis] wrote in to tell us about his “hack”, making an AB Audio Amplifier. The advantage of this particular amp is that the transistors never turn off, which would cause distortion. A full schematic is given in the article as well as a parts list. A complete “bill of materials” makes any circuit building project easier, especially for the beginner.

Although this is by no means a new circuit design, (a similar setup is used in car audio equipment) [Dino] does a great job of explaining how things work in the article itself and in the video after the break. He also gives some great tips about transferring your drawn circuit to a breadboard in a neat and organized way at around 5:00 in the video.

[Dino] tries to come up with something like this every week, so be sure to check back on his aptly-named site, Hackaweek.com for more fun stuff like this. Also, he mentions using the “free music archive” for his videos. This looks like a good resource for those that want to make other videos like this and need some music that legally doesn’t have to be paid for.

Filed under: how-to

Power Up with Knowledge

noreply@blogger.com (dB) — Wed, 17 Aug 2011 18:45:00 +0000

Power Up with Knowledge:

The LM317 is a favorite for many people who want quick, cheap, reliable and ajustable power. It only takes a few parts to set up and it does its job rather well. Sometimes though, you just need a power supply.While there are a million tutorials out there, not many go as in depth as [Phil] does in his 2 newest videos.

Covering everything from the wall outlet to the final output, [Phil] explains each part step by step, stating what it does and the math and formulas behind it all to produce quality results. He then goes over to a working model and reviews each part showing its real output on a oscilloscope, which is very handy if you do not have one yourself.

In the second video he takes that knowledge and builds it all up into a professional looking bench top model with LCD meter readout and varnished paper to complete the front look. If you’re looking to build your first bench supply or want a better grasp on what exactly is happening in the one you have now, you should join us after the break for these 2 quality productions.

Filed under: tool hacks

Clicking and counting with push wheel switches

noreply@blogger.com (dB) — Wed, 17 Aug 2011 18:42:00 +0000

Clicking and counting with push wheel switches:

Push-wheel switches are somewhat older technology, but [John Boxall] from the Little Bird Electronics blog shows us that they are still quite useful today.

In a quick but thorough demonstration, he discusses how this input technology works, showing off both single digit and multi digit inputs. The former is pretty straightforward, with each of the counter’s outputs tied to an I/O pin on his Arduino. Using multiple counter units is ever so slightly more complicated, but the job is made easier through the use of an NXP 74HC4066 bilateral switch. He shares a snippet of Arduino code that toggles through each of the switches, reading in their values one by one.

His walkthrough is a must-see for those who are just getting their feet wet with Arduinos and various input methods. These counters are great for 1-4 digit input needs, but if you require more digits [John] says that a 12-digit keypad would probably be a better way to go.

Stick around to see a short video demo of the switches doing their thing.

Filed under: arduino hacks

GeekWire Radio: Airbags in your phone, checking in on Google+, and iPhone vs. Android apps

noreply@blogger.com (dB) — Sat, 13 Aug 2011 20:37:00 +0000

GeekWire Radio: Airbags in your phone, checking in on Google+, and iPhone vs. Android apps: "

On this week’s GeekWire radio show and podcast, we offer a reality check on Jeff Bezos’ plan to put airbags in mobile phones; check in with Google+; talk about the rise of the Seattle-based Zulily daily deals service; and take a ride in the Uber private driver service.

Then we bring app developer Mike Schneider and AppStoreHQ‘s Scott Blanksteen into the studio for a discussion of the current landscape for mobile apps. And in our final segment, we have a new installment of Name that Tech Tune, with a chance to win a limited-edition GeekWire laptop sticker.

Listen to the full show above or directly via this MP3 file. You can get every episode of the GeekWire show using this RSS feed, or subscribe in iTunes or Zune.

Headlines and links related to the topics we discussed …

Jeff Bezos wants to put an airbag in your smartphone

Study: Google+ winning over suburban parents, losing college kids and cafe dwellers

Confessions of an Uber driver: An inside look at Seattle’s new private driver service

Daily deals site Zulily raises $43 million at a huge valuation of more than $700 million

Scott Blankstein and Mike Schneider

Links to some of the apps Scott and Mike discussed:

Photosynth

Camera Plus

ProHDR

Postagram

HBO GO

Glympse

Dragon voice recognition

ESPN ScoreCenter: iPhone, Android

FanGraphs

Check out the AppStoreHQ service; and follow on Twitter @appstorehq. Also see Scott Blanksteen’s guest posts on GeekWire.

Michael Schneider’s site: This is Tech; follow on Twitter @hivebrain.

Name That Tech Tune: Can you identify this very brief clip?

FCC BUREAU CHIEF: DON’T COUNT ON NARROWBANDING WAIVERS

noreply@blogger.com (dB) — Sat, 13 Aug 2011 20:34:00 +0000

Speaking this week at the Association of Public Safety Communications Officials conference in Philadelphia, David Furth — deputy chief of the FCC’s public safety and homeland security bureau — cautioned operators of land-mobile-radio (LMR) systems operating at 512 MHz and below that the commission’s Jan. 1, 2013, deadline for narrowbanding those systems isn’t going to change.

“This deadline is out there, it’s in the commission’s rules and it’s not going to move,” Furth said.

Narrowbanding refers to the process of converting a system’s channel widths, from the current 25 kHz to 12.5 kHz, to facilitate more efficient use of available spectrum. The ultimate goal is 6.25 kHz-wide channels, but the FCC has yet to set a deadline for that.

ON-DEMAND WEBINAR: Narrowbanding: Funding, licensing and deployment

The FCC has stated often that it is prepared to enforce this rule, perhaps by fining non-compliant agencies or — in extreme cases — shutting them down.

READMORE view full news

70 years of ribbing, hamming and wedded bliss

noreply@blogger.com (dB) — Sat, 13 Aug 2011 20:22:00 +0000

Bob dan Dorothy Truhlar, yang akan segera merayakan ulang tahun ke-70mereka, gambar diambil pada hari Rabu sore 3 Agustus 2011 di ruang ham radio rumah mereka di lingkungan Beverly Chicago, Illinois.

Bob dan Dorothy Truhlar mengatakan, bahwa mereka jatuh cinta pada pandangan pertama.
"Tapi aku tidak bisa benar-benar ingat," kata Dorothy, 89,.
After all, that was a long time ago. Come Aug. 16, the Beverly couple will have been married for 70 years.
“We have stamina,” Dorothy assures.

Full story: The Southtown Star

View Gallery

Macon sang petualang didunia Ham

noreply@blogger.com (dB) — Sat, 13 Aug 2011 19:42:00 +0000

Macon man ambassador for ham radio

Jimmy Griffin dapat melakukan perjalanan di seluruh dunia setiap malam tanpa meninggalkan kursinya.
Dia tidak pernah berkunjung ke salah satu negara di mana sinyal radionya bisa didengar. Bahkan, ia belum pernah bepergian ke luar negeri, menyeberangi laut atau bahkan benua lain.

Dia telah menginjakkan kaki dalam waktu kurang dari selusin negara, kebanyakan dari negara yang berada di Selatan.

Ham radio sehingga telah tiketnya ke tempat-tempat seperti Jepang dan Irlandia. Sejak 1990, ia telah membuat lebih dari 19.600 kontak dengan 3.063 operator ham di 40 - 50 negara.

Siapa yang butuh Facebook ketika Anda bisa berteman seseorang di Mesir pada sideband tunggal? Atau mendengarkan derak suara dari Cekoslovakia yang dipetik dari langit?

Jimmy 83 tahun dan tinggal di The Cottages di Wesleyan. Dia dan istrinya, Christine, akan merayakan ulang tahun pernikahan ke-61 mereka pada akhir bulan. Dia adalah anggota aktif dari Macon Amatir Radio Club, salah satu organisasi tertua di dunia amatir radio.

beritanya lengkap dapat di simak di: http://www.macon.com/2011/08/12/1662914/macon-man-ambassador-for-ham-radio.html

Building a computer out of 555 chips

noreply@blogger.com (dB) — Tue, 09 Aug 2011 19:10:00 +0000

Building a computer out of 555 chips: "

[M. Eric Carr] came up with an interesting build for the 555 contest earlier this year, and we’re pretty sure that it would have kicked the winner of the complex category off the throne if it were completed. Although it’s a few months late, we’re happy to feature at least part of his 555-based computer on Hack A Day.

[M. Eric Carr] started off implementing Boolean logic with a 555. After building a universal gate, he moved onto putting one bit of memory in a single 555. This design uses the 555 as a latch and is one of the craziest off-spec uses of a 555. While fitting 24 bits of memory on 5 large bread boards may seem like a waste, it’s a far cry from the square feet or acres of other computer builds we’ve seen.

From the post on the 555-based memory, [M. Eric Carr] says a completed design of his computer could be up and working this summer. It’s already August, so we’re hoping he’s still working on his design. Check out the video of the memory below.

Filed under: classic hacks, hardware

Quick and easy audio preamp

noreply@blogger.com (dB) — Tue, 09 Aug 2011 19:08:00 +0000

Quick and easy audio preamp: "

The most recent installment of [Dino Segovis’] Hack a Week covers the construction of a simple NPN transistor audio preamp. Some time ago, he built a small audio amplifier using an LM386 which worked well, but didn’t quite get his music as loud as he would like it. He decided to build a preamp to complement his amplifier, and demonstrates how you too can build one with just a small handful of components.

As the name probably suggests, the cornerstone of this amplifier is an NPN transistor. He explains that a forward bias is applied to the base-emitter junction, which results in the transistor operating halfway between its cut-off and saturation regions. Both halves of the input audio signal are superimposed on this bias voltage, resulting in a decent amount of gain across both channels from a relatively small package.

The preamp isn’t going to win any awards among audiophiles, but it is definitely a great beginner project. Its a novel way of demonstrating how transistors work, while producing a useful takeaway piece of audio equipment at the same time.

Continue reading to see a video showing just how big an effect [Dino’s] NPN preamp had on his music.

Filed under: classic hacks, musical hacks