On Mon, Mar 24, 2025 at 12:23 PM, gm0uhc wrote:
Anyway ... everything is working fine. Press the PTT in AM mode and you get 20W of carrier ... apply an appropriate audio signal, the ammeter on the PSU drops from 3.5A to 2.5A and the power drops to 8W.?
Thats not quite right , the residual carrier should be lower than peak-out , as the pa is linear, its presented with a generated spectrum, by allowing carrier leak through , the carrier side band levels are determined by the? drive levels , no mixing should take place in the? PA, at a guess, the? set will? be generating a lot of splatter ??
?
its possible to have a? mod index greater than '1' , but, the? negative swing will? not pass ''zero'' on peaks the? side band/carrier ration will? exceed normal proportions on peaks, this give higher ' apparent modulation level'?
?
something? is 'wrong with the? drive levels ... or the? pa linearity ?
?
73-Graham
g0nbd?
