Hi Joel, 20 dB will not be good enough to decode all transmissions, depending on the modulation parameters. In the lab you should at least be able t get 28- 30 dB, with a good path on a real transmission at least 24- 26 dB SNR. You can check some results on the DRMRx forum, i.e. this thread: http://www.drmrx.org/forum/showthread.php?t=1143&page=105&highlight=1296 which was mode A with 26 kbps.