Tuesday, March 17, 2009

The SDR ... Its Alive !!

Hello!

After some QRL , I found some time to work on my SDR Receiver which i have mentioned about in my earlier posts. After adding a BC 547 RF Preamplifier, I connected it to my PC and fired up M0KGK's SDR decoder and voila .... I picked up this transmission from a "french" (Not sure) Station. It still needs tweaking and boxing up but alas, It fianally works.

The Preamp is powerful enough to bring in weak stations with just a 3 Mt wire thrown around the room!

A well deserved break , I should Say!!

73's

Ragav

Sunday, January 25, 2009

Back after a long spell ....


Hello!!
Its been a long time since i updated this blog.
Almost a YEAR!!!!
College QRL had kept me from my shack and i decided to break the spell and attended a Software Defined Radio Workshop By VU3WJM, OM Rahul. Anna University, Chennai had done a great job of arranging a workshop to promote SDR's here.

Shyam, 3UBR and I got a kits of a simple SDRx for homebrewing. Since Shyam's Interest in the subject is simply too high, I took some tips from him which gave me a lot of things to think about before I could say "Yeah....I think I understand now..."

Once back in the shack after a brief dinner, I set my sights on the kit. I quickly put together the 5V regulator section and tested it. Next were the Jumpers on the board. After some struggling the jumpers were soldered on. Next were the Resistors, Followed by the non-electrolytics. Then came the IC sockets. The electrolytics and the Crystal were soldered only after the 2 transistors.

After a short break I returned to the shack with the pin layouts of the 3 IC's :
  1. 74HC74
  2. 74HC4053
  3. NE5532
The Pin voltages were measured and were found to be well within the specs of the IC's. Next in line were the 2 transistors. No problems there. Frequency measured was at 28.325 Mhz.

Close enough!

Now to interface it with a good PC (My laptop lacks a Line IN).

I have M0KGK,Rocky and WinRad installed. Lets see :)

73's

Ragav

P.S.: I also got the New BITX v3 PCB from VU3SUA and WOW... look at it guys!! absolute fun to assemble! More on that later!!!