USB digital modes interface

The September 2010 addition of the RSGB RadCom magazine, has a simple project for a USB digital modes interface. You can purchase back issues of this magazine from the RSGB website. The article was written by Dave, M5TXJ, and some follow-up information is available on his website HERE. I can’t reproduce the article on this blog due to copyright but here are some images of my construction of this project.

I made the PCB myself by printing the tracks using a laser printer and then ironing it on to a thoroughly cleaned copper clad board. I bought some acid crystals from Maplin and made up the evil concoction in my shed. The etching process took about fifteen minutes.

I was unable to source the relay used by the designer so I used a different type but mounted it under the board.

The USB sound card was sourced from eBay. Because I was using a double sided USB socket in my box, I needed to modify the soundcard to fit in the confined space. The USB plug was easily de-soldered and a short length of ribbon cable inserted.

I’m not a fan of hard wired cables so the box has plenty of sockets.

Here are some images of the internal wiring. I have kept the runs neat and tidy to make maintenance easier in the future.

I found this project easy to build and found most of the components easy to source. The only problem I had was a duff Op amp which once replaced allowed the circuit to burst into life. I hope to upload some video footage soon of this device being used, so keep watching.