8558B
 

Have an 8558B (Serial # prefix=2332A) that seems to work fine except that it
indicates ~ 30 dbm low. Any suggestions as t what might be the cause?

I suspect the U1 diode pair in the 1st LO. 1) How to test same? 2)
appropriate replacement diodes if indeed they are bad?

Please advise

-georgeK KB1HFT