It is possible that you are experiencing harmonic radiation from something that
"just got plugged in" (you know...a new chrismas present). I would suggest
tuning in the carrier on 6m and unplugging one electrical appliance at a time.
Do this even if the appliance is "off", because many now have "instant on"
circuitry that stays "RF hot".
Secondarily, computer monitor boards and cables are notorious for generating
harmonics...especially when they are driving a monitor no a "non-native"
You can probably take it from here.
Ev Tupis, W2EV
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