Some stage is probably oscillating to make the added signals. I've seen
that in a prototype Motorola receiver we were using for our local
repeater. A proper parasitic suppressor cured it. Else the PLL loop
filter has a badly wrong value capacitor and its doing the oscillating.
Since it is in both transmit and receive its probably the PLL running
amuck. It should show on Tentec's spectrum analyzer or another receiver.
It might come from a board not being properly grounded. In many other
radios that often causes such spurs.
73, Jerry, K0CQ
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Entire content copyright Dr. Gerald N. Johnson. Reproduction by
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