AnsweredAssumed Answered

8563E has gaps in frequency coverage

Question asked by w3sz on May 11, 2017
Latest reply on Jul 10, 2017 by MikeM

I have an 8563E that recently stopped detecting signals on certain frequencies.


I have discovered that the LO signal at the front panel LO SMA connector is absent (or weaker than I am able to detect with a 437B power meter) on those frequencies where the SA does not detect signals. On those frequencies where the SA is working properly, the LO signal strength is within specs with an output of 14.58-15.95 dBm.


The error messages that I see are generally YTO-related as well: 319, 334, 356.


I suspect that this dysfunction is a result of failure of the YTO, but I am not sure where to proceed from here. I have the Service Guide 08560-90149 and I have read it but I am still not sure of my next step.


The frequencies where things are properly working include:
200 MHz
300 MHz
880-2800 MHz
5 GHz
8-12 GHz
18.9-24 GHz.


The frequencies where there is no LO signal and the SA can detect no signals are:
100 MHz
400-870 MHz
2.9-4 GHz
7 GHz
15-18.8 GHz


I would appreciate any help from the group in guiding me on how to proceed from here.

Thanks in advance and best regards,


Roger Rehr