AnsweredAssumed Answered

8753C noisy source...any guidance?

Question asked by michaelh310 on Apr 29, 2015
Latest reply on Sep 5, 2015 by michaelh310
My new-for-me 8753C seemed at first to be working well, but I noticed noise in the output trace.   It failed the trace noise test (standard: 0.006 dB, observed varies, typically 0.05 dB or so)

I found substantial variation in the output level of the reference (approaching a dB) and lots of phase noise, worse at higher frequencies.   It's like it's just barely in lock.

I've done tests 44,45,and 48 and they don't seems to help.  I've tried using a different input channel, no change.  I've wiggled and adjusted all the RF cables.

Any further guidance?  I figure it's either in the source module (grrrrr) or the feedback loop.

I don't see any temperature dependence.   Below about 1 GHz it's not too bad, gets progressively worse above.

Thanks in advance.