[Test-Equipment] HP 8656A question

Tue, 22 Jul 2003 07:19:10 +0200

The 8656A is notorious for its excessive phase noise.
I have access to a HP8656A at work which shows similar FM in the low
frequency ranges as well. It seems to be normal for this this type
of generator.
When you slap it slightly with your hand, you hear the
PLL unlock an regain lock in the receiver.
The 8656B und 8657A/B are supposedly (somewhat ?) better.

    Gottfried OE1IRA

John Miles wrote:
> 
> The 8656A isn't the cleanest synthesizer around, so the FM noise may be
> normal.  I'll try to have a look in the manual for mine tonight and see what
> the specs look like.  Do you have a spectrum analyzer or some other way to
> actually measure the FM?
> 
> -- john KE5FX
> 
> 
>>-----Original Message-----
>>From: [email protected]
>>[mailto:[email protected]]On Behalf Of Carl Walker
>>Sent: Monday, July 21, 2003 4:10 PM
>>To: [email protected]
>>Subject: [Test-Equipment] HP 8656A question
>>
>>
>>Hello to the list.
>>
>>I'm the proud owner of an HP 8656A signal generator, but it seems to be
>>suffering from a bit more residual FM than I would like - but only below
>>100MHz.
>>