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pb1433 rf board output of Q104 board pin 14 going into t3 is a beautiful sine wave. output of t3 going to board input pin 15 is trashy noisy. I sprayed the band selector wafers with deoxit and gave it a good workout but it is still the same. dirty signal.
what can i do to fix this?? Is the noise caused by the resistors??
The board produces no tx output. SN7400 output is good, Q106 swapped out with a good one, rf no output, Q105 replaced with a good one, no output.
removed Q105 and q106. Placed good rf board and bad one side by side and ohmed it out compairing readings and are reading identical.I am at a loss, it should work but does not. !!.

anyone with RF board experience advice would be greatly appreciated.

Thanks, Robert KH2BR

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It takes time for the deoxit to work. now, this morning noise is gone. I tried to measure the output of the mixer Q101 on the good rf board with a scope and I could not see anything. Dont know why. I ordered a new mixer for the bad rf board hoping that will solve the no rf output. Q104 has little output on the bad one but high output on the good one. I tried peaking the trimmers for T1 but on the good radio they have no effect on the output power. The capacitor bank for T1 is for receive. There is a mistake in the schematic. In the schematic I have rx in and tx out are connected togather so I need to go back and re-tweek the RX trimmers

Problem solved. !!? Replaced mixer IC and a couple of diodes. RF board is now working