We did not test MT63, because only MT63-2000 could work with flarq and ARQ, and we think it would be irresponsible to use that on the shared ham bands for the little benefit it would bring compared to much more narrow modes. It is OK to use on MARS, because each MARS frequency "channel" is dedicated, not shared (well, "time-shared" by different nets", and the channels are voice-bandwidth as they are also used interchangebly with voice. My experience with MT63-1000 on MARS is that it works very well under QRM and static, as expected, but that is with S5-S9 signals in the South Carolina - Florida corridor, and weaker stations often report "negative copy", probably because the S/N is not good enough at their locations. Will find out more about the MT63-1000 real-world static resistance as summertime approaches.
73, Skip KH6TY http://kh6ty.home.comcast.net ----- Original Message ----- From: Tony To: digitalradio@yahoogroups.com Sent: Sunday, March 22, 2009 3:03 AM Subject: Re: [digitalradio] THOR is static-proof (Re: KV9U - MT63) Skip, >MT63-1000 has a -5 dB minimum S/N, but MFSK16 has a -13.5 dB >minimum S/N, so the static tests you made must be at signal levels >high enough that MT63-1000 decodes, which may not be a realistic >level. That is true. Fortunately, there are times when signals are above the decode threshold for the majority of modes. That gives us the chance to test the higher throughput modes to see what works in heavy static. >MFSK16 turned out (after three months of testing) to be the most >static-resistant mode of all That is interesting Skip. It did seem to do slightly better than THOR22 during n simulated tests. Did you see any advantage in throughput with MT63 during the static crash tests when signals were adequate? Tony -K2MO
