PLLs and phase noise

I'd love to give you a fair answer, but as it stands, the question is far too vague. PLLs can be very good at detecting a signal buried in noise, but the devil is in the details. What are you trying to do?

Jeroen Belleman

Fix my spectrum analyzer. It's a complex beast and it has a YIG-tuned oscillator stage which is out of lock. its IF is all over the place; not just jittery but out of band, and I have to find out why.

I suppose the first thing to look at would be the power supplies of the relevant section. Can you also get a look at the tuning voltage of the YIG?

Jeroen Belleman

Am 21.07.24 um 23:01 schrieb Jeroen Belleman:

current!

Is is also in the US, that the news volume has dropped to nearly nothing?

Gerhard

OK, sure.

CrowdStrike struck down the crowd of MS-Windows servers? Let this be a lesson.

Jeroen Belleman

Ideally the current is what's relevant here. It should be between 50 and 150mA. However, measuring that is a little bit tricky, so they provide a test point for the voltage instead, and that does indicate what appears to be the correct behaviour. But that's just an aside, since the problem lies upstream from the coil driver.