I have a general question probably related more the vara modem itself then about VarAC. I have not fully understood the relationship between S/N and speed levels; indeed I had qso's with +10 dB and received +00 dB and maximum level at 88 bps, while sometimes even with S/N much lower i have seen up to 270bps. Can anybody tell me more about it?
73 de Phil, iz1fks
Of course the non-registered versions are limited in their connect speed.
Generally the better the SNR the better the speed can be. Here is a good read from the Winlink team with graphs.