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: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] 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: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] 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@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@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@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.