[time-nuts] Re: DIY Low offset Phase Noise Analyzer (Erik Kaashoek)

[Bob kb8tq]

Hi

As noted in another post, the phase detector guys talk
about a figure of merit that is not directly comparable to 
the floor of a DBM. If I translate the -170 dbc/ Hz at 100MHz
on the DBM, to the PLL chip FOM, I would add 80 db. That
would make it a -250 dbc FOM vs the -231. 

Since the FOM stuff does not really apply to a DBM approach,
you would never see this done. One works one way, the other
works in a very different fashion. 

Bob

> On Jul 8, 2022, at 8:19 PM, Mike Monett via time-nuts <time-nuts at lists.febo.com> wrote:
> 
> To Bob kb8tq. You wrote:
> 
>> Hi
> 
>> The noise floor of the double balanced mixer (used as a phase
>> detector at 100 MHz) is in the -165 go -170 dbc / Hz range. I've
>> used the parts you are talking about. Their floor is *way* higher.
> 
>> Bob
> 
> I stated the MC100EP140 would not match the Hittite HMC984LP4E. It has 
> -231 dBc/Hz noise.
> 
> -231 dBc is *way* lower than -170 dbc. About 60 dB lower.
> 
> You might be interested in trying it. Only $13.25 at Arrow:
> 
> https://octopart.com/search?q=HMC984LP4E
> 
> Thanks,
> 
> Mike
> _______________________________________________
> time-nuts mailing list -- time-nuts at lists.febo.com
> To unsubscribe send an email to time-nuts-leave at lists.febo.com