I would like to remind all, if you are not already aware, to turn AGC off when static crashes are an issue. If you are fortunate enough to operate in a mixed mode net, turn it to fast, or for inland stations, medium. Slow recovery time of the rig in response to a strong signal cannot be corrected by a sound card protocol; no matter how robust. While we are at it, when using MT-63 at 1K long, keep in mind that most software hard codes a starting frequency of 500 Hz, and that is a 1.5Khz total width. It doesn't work well if you have your filters set for PSK, or a narrow-band mode. In running digital training nets for newcomers to MT-63, it is absolutely amazing how many ways can be found to lessen it's effectiveness; primarily due to not understanding where the signal is, where it is going, and how it is getting there. It took me a long time to factor out many of the common reasons it didn't work. That is one of the main reasons that PSK-31 is so popular; even a caveman can do it. (Sorry Geico; couldn't resist) David KD4NUE
-----Original Message----- From: digitalradio@yahoogroups.com [mailto:digitalra...@yahoogroups.com] On Behalf Of Tony Sent: Sunday, March 22, 2009 3:04 AM To: digitalradio@yahoogroups.com 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
