[time-nuts] xtal oscillator phase noise

Mike Feher mfeher at eozinc.com
Tue Jan 1 14:11:33 EST 2008

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

-----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


Good timing; yesterday, John Miles was over here to test some ULN.
Here's a Wenzel ULN 5 MHz against a ULN 10 MHz.
(these are relative measurements; absolute would be ~ 3 dB better)

Also, for those interested, two 8607-08 BVA against each other:


time-nuts mailing list -- time-nuts at febo.com
To unsubscribe, go to
and follow the instructions there.

More information about the time-nuts mailing list