In a message dated 5/10/06 7:26:42 PM, [EMAIL PROTECTED] writes:
> I use a T-368 PTO as my main station vfo. I stabilised it by running the > filaments off a regulated DC supply. Also use it to run mic preamp. Now > have stable VFO and hum-free microphone preamp. I'm not sure why a small > fraction of a percentage variation in filament voltage will cause such > noticeable drift. Without the regulated filament voltage, neither the A4 > nor the T-368 pto are stable enough to work 40m cw using a narrow filter. > > T-368's following the "Basic" model included a constant voltage xformer for the PTO filaments. Dennis D. W7QHO Glendale, CA
