David, >I would like to remind all, if you are not already aware, to turn AGC > off when static crashes are an issue.
Good advise. A fast AGC setting may help as well if there's no way to turn it off. Tony -K2MO ----- Original Message ----- From: "David Little" <dalit...@bellsouth.net> To: <digitalradio@yahoogroups.com> Sent: Sunday, March 22, 2009 9:58 AM Subject: RE: [digitalradio] THOR is static-proof (Re: KV9U - MT63) >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 > > > > > >
