Just a quick thank you to all who responded to my call for help on the hum
problem.
The most consistent opinions centered on common mode hum. The quote below
from Ron, AC7AC, summarizes what several messages said -
"What is happening is that some of the local oscillator signal is getting
into the power supply where it is modulated by the a.c. in the rectifier
diodes, then it is being re-radiated by the wiring and picked up in the
receiver antenna circuit. Of course, the local oscillator signal in a
direct-conversion receiver is on the receive frequency, so the receiver
finds a signal modulated by hum following it no matter what frequency you
tune it to."
Once I try some of the suggested solutions, I'll drop a note to the reflector
with results.
Thanks again to all, I have read each email carefully, and really appreciate
the inputs. There is a SUPER group of people on this reflector.
73 & Happy TT'ing
George Maier - K1GXT
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