[time-nuts] 20logN was Re: phase noise questions (long)
bruce.griffiths at xtra.co.nz
Wed Jan 23 19:53:12 EST 2008
Mike Feher wrote:
> Bruce -
> I am just trying to keep things practical for us. - Mike
> Mike B. Feher, N4FS
> 89 Arnold Blvd.
> Howell, NJ, 07731
I realise that, but some caveats are necessary, otherwise someone will
try locking a low frequency VCO to the rubidium resonance at (6.83?)
GHz by using a frequency multiplier chain to generate a 6.83GHz
carrier. They will then wonder why it doesnt work, not realising the
frequency multiplied carrier may have collapsed.
If one is aware of the carrier collapse phenomenon, then the required
VCO phase noise spec to avoid it can be worked out beforehand.
In most other cases the simplified analysis works well.
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