[time-nuts] xtal oscillator phase noise

[Mike Feher]

BTW, I remember when I was on a program and the initial oscillator was
specified at 5 MHz. When we changed it to 10 MHz, all of the vendors wanted
a 6 dB allowance on PN. - Mike

 
 
Mike B. Feher, N4FS
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960
 
 

-----Original Message-----
From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com] On
Behalf Of Mike Feher
Sent: Tuesday, January 01, 2008 2:12 PM
To: 'Tom Van Baak'; 'Discussion of precise time and frequency measurement'
Subject: Re: [time-nuts] xtal oscillator phase noise

Tom -

Nice data. It really confirms what I initially posted. Your measurements
were at 5 MHz, so, the expected number at 10 MHz would be 6 dB worse. The
-155 dBc/Hz number quoted by memory from me then was not that far of at all.
- Mike

 
 
Mike B. Feher, N4FS
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960
 
 

-----Original Message-----
From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com] On
Behalf Of Tom Van Baak
Sent: Tuesday, January 01, 2008 2:02 PM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] xtal oscillator phase noise

> For what it's worth, the Wenzel 5 and 10 MHz ULN oscillators are
> generally considered to be about the lowest noise oscillators
> commercially available.  They really shine in their noise floor.
> There's actually (at least) one 5MHz oscillator with a better 1Hz offset
> spec -- the Oscilloquartz 8607-08 BVA at -130 dBc/Hz, though its noise
> floor at about -160 dBc/Hz is nothing like the Wenzel's.
>
> Here's some data on the Wenzel units from their web site:
> 
> 5 MHz 10 MHz
> 1 Hz -120 -105
> 10 Hz -150 -135
> 100 Hz -170 -160
> 1 kHz -176 -173
> 10 kHz -176 -175

John,

Good timing; yesterday, John Miles was over here to test some ULN.
Here's a Wenzel ULN 5 MHz against a ULN 10 MHz.
http://www.leapsecond.com/museum/wenzel-uln/uln5-uln10.gif
(these are relative measurements; absolute would be ~ 3 dB better)

Also, for those interested, two 8607-08 BVA against each other:
http://www.leapsecond.com/museum/osa8607/8607-8607.gif

/tvb


_______________________________________________
time-nuts mailing list -- time-nuts at febo.com
To unsubscribe, go to
https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.


_______________________________________________
time-nuts mailing list -- time-nuts at febo.com
To unsubscribe, go to
https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.