Saturday, February 11, 2012

Ensemble RXTX Software Defined Radio transceiver

On the bench at the moment is the Ensemble RXTX SDR. I've built a Softrock receiver in the past but never tried transmitting so this should be fun. I'm building it to cover 20m, 30m and 40m which seems a pretty useful range.

It's a bit hard to order a Softrock, the site often says "check back soon". I happened to be reading the reddit amateur radio site when someone noticed stock so I got in.

There's still a bit to go but I'm now up to the point where I can try the receiver.


(That photo is from before I was ready to try the receiver). The hairy thing for me with these kits is the soldering of tiny surface mount components but I find that I'm getting better (although probably using too much solder) and also the components seem very robust.


Not too bad eh? (Believe me, it's really tiny).

This model has an Atmel processor which does USB so that the computer can control the frequency and transmit line.

My build has not been all smooth sailing. On receive it was super deaf - turned out I'd wound the wrong T5 and it was attenuating the receiver so much that it made almost no difference when the antenna was connected such that I thought something was unconnected.

There's not many stations on but here's a video of a little reception that sounds pretty good, until my WSPR station transmits and blots everything!


Here's a bit more reception:


The Kodak Zi8 does a pretty good job on these clips I think.

3 comments:

panda said...

Great surface mount soldering Peter
73
Ian VK2IJ

Peter Marks said...

That's kind of you Ian. I think I'm using too much solder though and my iron needs filing down. Getting there though.

Bruno Keymolen said...

Thanks for that post Peter!

Bruno kd2ere