It seems that the wheel has to be rediscovered periodically. For me, the solution is to use a PEP wattmeter and always run the output power slightly below the clipping level, where the meter needle advances no more. This point may be different on different bands. Just identify the clipping level and back off a bit, if there are no other distortion contributions and your system is linear to the clipping point.
With ALC, it all depends on its particular design, and avoiding ALC action avoids the distortion introduced by fast attack fast decay ALC. As with receivers, what is needed is a fast attack slow decay ALC, no nonlinearities between the transmitting and receiving soundcards and peak reading capable meters, if you run digital modes with an envelope. I built a peak detector for my output meter and now I can measure either peak or average power, at will. As simple as that. 73, Jose, CO2JA Andrew O'Brien escribió: > > > > The replies to Ralph's question about audio levels appear to be sound > advice and certainly in keeping with what has been advised since sound > card digital modes burst upon the scene. I wonder how accurate it is > though? I have seen a few serious hams argue that "no ALC" is not > really the case, that some ALC can be OK. I have also seen mention > that the no ALC issue applies to some modes (like PSK) but not to > others like (JT65A). I also wonder about the half-power advice that > some advise. With my homebrewed interface, I could never get much > above 40 watts before some ALC began to show. When I switched to a > commerical interface with good isolation (Microkeyer by Microham) I > can almost always get 100 watts output without any ALC action. I have > not received any negative reports about my signal . If I run 100 > watts SSB for phone contacts, why would I not want to do the same for > digital modes assuming the signal was "clean" ? . Yes, I would agree > I should not run 100 watts if communication was possible with less > power, but I don't think a brief PSK CQ at 100 watts is going to do > much more harm to my finals than a 3 minute ragchew at 50 watts, phone > . Right ? > > Comments ? > > > > -- > Andy K3UK > Participe en Universidad 2010, del 8 al 12 de febrero de 2010 La Habana, Cuba http://www.universidad2010.cu --------------------------------------------------------------------- SEGUNDO SEMINARIO INTERNACIONAL LEGADO Y DIVERSIDAD. ARQUITECTURA Y URBANISMO. El rescate de los valores urbanos y arquitectónicos en tiempos de globalización Colegio de San Gerónimo, La Habana Vieja, noviembre 24-27, 2009 ---------------------------------------------------------------------
