Walt, I think there is no doubt that this is true. The question I have been struggling with is how much is enough/too much. I guess what I am looking for is a curve showing bandwidth vs. throughput for parallel tone modems, or maybe more precisely where is the point of diminishing returns? I am sure there are many factors that would affect the curves. I know from experience that MT63 is a great mode when making very long and many hop contacts. I have watched the fading move across the waterfall, and my text be 100% correct. I am sure that this is because of the redundancy of the code spread out over many frequencies. MFSK16 sometimes performs better under certain conditions with a quarter of the bandwidth. What my question boils down to is generally, what is the accepted maximum bandwidth of any signal in the Amateur HF bands, given the finite spectrum and many interests?
73, Mark N5RFX >Research done by "independent research labatories and universities" >confirm that the best bet to increase throughput and robustness on >HF channel modems is to use parallel tone modems.
