We had a complete breakthrough on the Odyssey Siren in the past two weeks. It will be used in Suitsat 2, in a terrestrial linear repeater experiment by Viktor Kudielka OE1VKW and friends, who supported its development, and we are already leaping all over the place to applications.
Frank Brickle and I will be doing our SDR code on it over the next several days. The board as shown in the schematic needs some modifications to fix the 3 - ish volt power supply for the Codec and a modified oscillator circuit but we are certain it will all work now.
On the 10.7 MHz IF, I measured 0 dBm max into a 50 ohm load and less than -120 dBm MDS and > 80 dB dynamic range. This is with a BOM of < $50 in parts and about a $20 dsp pic chip!
Yesterday in Rick's lab, with W2GPS, K3IO, we made the above measurements, hacked on code and turn the thing into a bent pipe transponder. I also did the hilbert transform to make it an inverting transponder. It all worked perfectly.
http://www.cnssys.com/~w2gps/amsat_files/suitsat/
has detected audio in an SDR-IQ SDR as well as captured IF from the SDR-IQ of the transponder. We have to balanced for image and do DC offset correction but the thing works and sounds great as you can hear for yourself!
73's Bob N4HY