Software Defined Radio - Projects

Over the last couple of months, I've done a bunch of stuff with Software Defined Radio.  I run Linux at home  and so I have been working with GNU Radio, and I've got a couple of different kinds of radio hardware, one being a TV Receiver USB Dongle (read about my adventures getting that working) that can be convinced to generate a data stream centered on some frequency between about 70 MHz and about 1700 MHz.  The other is a Softrock 40 R, which is a crystal-controlled quadrature downconverter that hears about 96 kHz of the 20m band centered around 14.070 MHz.

So far, I've mostly used the TVRO dongle to listen to FM Broadcast (87.9 MHz to 107.9 MHz in the USA)  and to the local repeater (147.2 MHz in Katy, Texas) and I've rigged up a CW Receiver for the Softrock.  I've been collecting my thoughts about SDR projects, and I thought I'd list a few of them.

Incidentally, it may not be intuitively obvious to the casual observer that the GNU Radio software isn't a radio application, it's a toolkit for producing radio applications.  It certainly wasn't intuitively obvious to me, but then I'm widely known as someone who rarely pays attention.

Anyway, the projects.  In terms of software I want to do these:

First, is a CW Skimmer like thing that works under Linux or just with the GNU Radio software.

The second would be a CW Skimmer like thing that does PSK-31 instead of CW.  Update:  I know such a thing exists.  See for example:  http://www.walter-dallmeier.de/software-by-dl4rck/rckskimmer/

Third would be a receiver that speaks rigctrld protocol (I looked, but I can't find a link) and can be used to receive satellite signals.

I think I'll start by implementing these things in Python and then convert them to C++ if it seems be an appropriate thing to do.

In terms of hardware, I want to do things like these:

A TVRO Upconverter so I can use the TVRO dongle for receiving HF signals.  This will likely require hardware modifications to the dongle.  I especially want to replace the antenna connector with an F connector or BNC connector or something.

In fact, I'll probably modify more than one of those dongles so I can use the UHF preamp I've bought and then so I can connect that preamp to an antenna with significant gain.

I also want to build a couple more kits, including the UHFSDR kit and ultimately I want one of those "nimblesig iii" devices I mentioned in previous blog posts.

That should keep me busy for a while, shouldn't it?