[time-nuts] Very challenging phase noise measurement, does anyone have an idea??
lists at rtty.us
Wed Dec 5 21:48:09 UTC 2012
A "3048" style measurement with the carrier suppressed by lock should do
pretty well. If the XOR's are out, there are a lot of mixers available that
work at 125 KHz. A simple op-amp buffer and a sound card could do what you
need to do.
From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com] On
Behalf Of Adrian
Sent: Wednesday, December 05, 2012 4:33 PM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] Very challenging phase noise measurement, does
anyone have an idea??
For phase noise the frequency range is 1MHz to 8/26.5/50GHz
The spectrum analyzer works from 20Hz to max.
Azelio Boriani schrieb:
> Isn't the FSUP a 110K euros equipment 20Hz-50GHz capable? 125KHz shouldn't
> be a problem. I had an FSUP for 25 seconds to play with... really
> impressive but too limited test time to appreciate fully.
> On Wed, Dec 5, 2012 at 1:14 PM, Bob Camp <lists at rtty.us> wrote:
>> Just about any of the high speed CMOS parts should work. A 74AC86 is
>> the earliest part I would trust. Any of the fast logic families that came
>> after that should do equally well.
>> On Dec 5, 2012, at 7:03 AM, Hans Rosenberg <Hrosenberg at catena.nl> wrote:
>>> Hello Time-nuts,
>>> I have to do a phase noise measurement and I'm wondering if anyone here
>> has any ideas on that. We have to measure the phase noise of a 125kHz
>> carrier (5Vp-p signal level). The measurement system should have a noise
>> floor that is -164dBc/Hz at a distance of 1kHz to 8kHz away from the
>>> Our current plan is to use 2 of these sources, have one in free running
>> mode and lock the other one to the first one using an XOR gate and then
>> the output of the XOR gate as an output signal. However, we are wondering
>> if any of you know a better idea. Maybe there is an off-the-shelf piece
>> equipment that can do that that we could rent. Or maybe we could increase
>> the frequency to a few megahertz using a pll, which means the signal
>> into the measurement range of our FSUP phase-noise analyzer. Problem is,
>> the phase detector would then need to have an insanely low noise-floor
>> our idea the XOR also has to have this insanely low noise floor as well
>> course) so does anyone have experience with anything like this? Does
>> know an XOR with these good specs? I don't have a clue what a standard
>> 74lvc1g86 would do. Needless to say the supply of this XOR would have to
>> ridiculously clean, but I do have a solution for that problem.
>>> Any help is greatly appreciated!
>>> Best regards,
>>> Hans Rosenberg
>>> time-nuts mailing list -- time-nuts at febo.com
>>> To unsubscribe, go to
>>> and follow the instructions there.
>> time-nuts mailing list -- time-nuts at febo.com
>> To unsubscribe, go to
>> and follow the instructions there.
> time-nuts mailing list -- time-nuts at febo.com
> To unsubscribe, go to
> and follow the instructions there.
time-nuts mailing list -- time-nuts at febo.com
To unsubscribe, go to
and follow the instructions there.
More information about the time-nuts