HP8591E phase noise question

[sp9bsl]

Hi all,
I have HP8591E analyser and while comparing it to some newer equipment like Siglent SSA3021X, I noticed somewhat high side noise of my HP. I can't find any screenschoot of such measurement one of the HP8590E series so, I'd like to ask here. This is measurement of CAL output (300MHz) available at the front panel. Cal signal was measured also with mentioned Siglent and it is much cleaner, about -90dBc at 2kHz offset from the carrier (same RBW, same VBW and span).

I unplugged the SMB connector from third converter (321.4 input) and signal measured on Siglent has exactly the same shape and 2kHz dBc value I see on HP. The 600MHz output to tripler has side noise about -90dBc at 2kHz offset - I think hits bottom limit of Siglent.
My analyser passes all calibration routines with no errors. HP spec says about side noise: <-65dBc at 30kHz so technically ok but... I'd be happy to see such measurement from another user.

Regards
Slawek

[Bud]

Here is a shot from my 8594E.

[sp9bsl]

Hi Bud,
Thank you! Looks close to mine. I think the few dB difference around 1kHz (and overall slight different "skirt") might be because of different (better) YIG in your HP.