50MHz 500Watts Linear Amp Using IRF510

I came across this site with a super design that uses 16 cheap IRF510 power transistors to get 500 Watts of RF power. Now, this is an Ideal amp for hams in India as these transistors are available very cheap over here.

Here is the link to the site. You can find the entire PCB layout, Schematics etc there.

http://frenning.dk/OZ1PIF_HOMEPAGE/50MHz_IRF510.htm

I have put this in my to-do list and in the mean while, i hope you like building it.

Labels: amateur radio, electronics, ham radio, HF, power amplifier, radio, RF, RF amplifier

Bitx20 Kit from VU3SUA

Yay!!, I received my Bitx20 kit from Sunil Lakhani(VU3SUA) today. I was jumping with joy as i received it. The postage + the time in transit was very normal. And he had included Front end coils, Balun Cores, Dumbbell cores, and a transistor that is a little difficult to obtain in local shops. He also sent me a free Frequency Counter PCB!!! I love this guy!!.

The boards were of excellent quality, some spacings are some times a little large and some time a little short, but its okay since it is totally designed here. The PCBS were all plated and masked. Very well made I would say.

Here are the contents.
1. 1x Bitx20 Main Board,
2. 1x Power supply and Linear Amp PCB,
3. 4x Front end Transformers (Already wound),
4. 7X Balun Transformer Cores,
5. 2x Dumbbell transformer cores,
6. 1X 2SC2570 Transistor.

The packing was excellent, he had taken utmost care to pack them properly with a polythene cover, then a paper cover (had a contents listing), and a thermocol protection around this cover and then all these covered in the standard cloth based packing used for Speedpost. Yes, I did spend a lot of time unpacking it :).

I will post the photos of the PCB as well as the contents of the kit in this post as soon as I can arrange a digital camera.

So, I am back to building the kit now, have fun :), and hang in there for more.

Labels: amateur radio, electronics, ham radio, HF, power amplifier, Power supply, radio, RF, RF amplifier

AVALA-01 SDR

AVALA-01 is an excellent monoband SDR (Software defined Radio, PC Controlled) design.
It was designed by Tasić Siniša (YU1LM), a Serbian Radio Amature.
His words. "New mono-band SDR transceiver AVALA-01 is ADTRX-2 transceiver with built in power amplifier and band oscillator all on one board. Transceiver is optimized for work with one sound card and Duncan M0KGK software. With unique PC control setup AVALA-01 is working in all other programs and with all types modulations SSB, CW, DIGITAL....also."

You can get the circuit details here.



You can get the printed circuit boards from Mr. Sunil Lakhani VU3SUA. His blog page with the details are here. Let him know that you have been to my site :).

Labels: amateur radio, electronics, ham radio, radio, RF, SDR

Bitx20 Transceiver

Here, I will explain briefly about this transceiver. This is a design done by Ashhar Farhan, an Indian Amateur Radio Operator and an electronics engineer. It is a bidirectional SSB transceiver. His original design can be found here. This is an excellent 20 meter radio which is quite cheap to build. You can build the entire thing within $15 or around Rs.650/- . You can also find another one of his designs here.

And once this design was released for the public, there were many enthusiasts who devoted their time and tweaked it to perfection. And they formed a Yahoo group called Bitx20. If you are interested in the project, I suggest that you sign up there. You will need a moderator to approve your subscription, but the wait time is negligible.

There are many kit manufacturers promoting this design and you can find some of them here.

QRPKits: A full kit for Bitx20. $90USD.
VU3SUA BITX: Pre wound front end coils and Balun cores, rest of the components has to be bought locally. $8USD or around Rs:300-350 including postage within India. Please contact Sunil Lakhani and he will send you the information required to purchase the board.

Here is a picture of his board.


Or, In case if you like to etch it yourself, the pcb layouts are available within the files section of the Bitx20 Yahoo! group.

So, thats it for today. Good luck on building your Bitx20. Have a good one.

Labels: amateur radio, electronics, ham radio, HF, radio, RF

Dealing with RF interference

Here is a guide that deals extensively into RF interference.

Here you go.

RADIO FREQUENCY INTERFERENCE (RFI) Notes
M.D.Lowell, N1LO October, 1998

Progress: Through July 1999 archive

Check http://www.qsl.net/n1lo.


Another very well documented guide here.

http://www.kyes.com/antenna/interference/tvibook.html

Make sure you make good use of these guides.

Labels: amateur radio, cable, computers, electronics, ham radio, hardware, HF, interference, radio, RF

Build your own Vacuum Tube?

This guy is crazy!!, He even makes his own vacuum tubes!!

http://paillard.claude.free.fr/

The page is in French, but use the Google translator link provided to read. Very interesting video there.

Labels: amateur radio, DIY, electronics, geek, generic, ham radio, hardware, HF, how to, radio, RF

Elektor 1987 20 meter SSB Receiver

Searching out this article took painstakingly long. This was featured under the retronics section in a recent Elektor magazine. Even though they said there is a free download of this article available in their site, there was nothing. It took long hours of search to pull it out from a cache. I am posting it here to save the trouble for any one interested.

Have fun with it people :)

87051u.pdf

Labels: amateur radio, electronics, ham radio, HF, how to, radio, RF

All bander!!

Here I found a simple receiver, very simple actually, to receive all nearby radio signals. Check it out, would take only 15 minutes to assemble and test :)


http://www.techlib.com/electronics/allband.htm

Cheers!

Labels: amateur radio, hack, radio, RF, simple

Hack your radio for Airband

Here is a simple hack you can do to your cheap AM/FM radio. With a few adjustments, you can receive AIRBAND (Flight to Tower Comms).


http://www.make-digital.com/make/vol09/?pg=29&u1=texterity&cookies=1

There are dedicated receivers for these and here is one from Elektor if you want to have a dedicated receiver.

http://www.elektor.com/magazines/2002/march/vhf-airband-receiver.55620.lynkx

Enjoy.

Labels: amateur radio, electronics, hack, ham radio, HF, radio, RF

Frequency Counter.

A nice freq counter.

While browsing the web, I came across a cool freq counter that you can add on to your home brewed radio. Here it is.

http://www.cumbriadesigns.co.uk/kits.htm

Enjoy!

Labels: amateur radio, DIY, electronics, ham radio, HF, radio, RF

Hooked on to Amature Radio.

The radio bug bit me again....

I have been modding, tuning many radio circuits these days to (mis)use them for other purposes ;). So the thought flashed again, why not take up the Amature Radio Exam and get a call sign and home brew a transceiver. So I am on it from the past few months. The biggest issue, is learning Morse code. One of the main criteria here to pass the ASOC exam.

Here are the details of the stuff I am using to learn for the Exam.

ABCs of Amature Radio, EFY Publications Rs: 75/-
G4FON Koch Morse code Trainer. (Free)

I have setup a 40 meter band simple dipole antenna. I will post the image, and constructions details here later.

Labels: amateur radio, electronics, ham radio, HF, radio, RF