); SAEximRunCond expanded to false Errors-To: [EMAIL PROTECTED] RETRY From: "Rick Karlquist" <[EMAIL PROTECTED]> Subject: Re: [time-nuts] Dumb question about SC-cut crystals Date: Mon, 22 Oct 2007 14:32:51 -0700 (PDT) Message-ID: <[EMAIL PROTECTED]>
> ); SAEximRunCond expanded to false > Errors-To: [EMAIL PROTECTED] RETRY > > A lot of work has been done in this area under the > designator "Microprocessor Controlled Crystal Oscillator" > MCXO, which is probably not a really great name. > Anyway, they are non ovenized and use SC cuts. I believe > the original FCS paper on them was around 1990. I found the use of the different tempco dependence of the 1st and 3rd modes an interesting way of measuring the temperature-dependent shift. By having a dual-mode oscillator setup and then mix the 1st mode frequency with the divided down version of the 3rd and then measure the beat-frequency. This can then be used in various ways such as resynthesis etc. It's in a long presentation of Vig. He shows a number variants of this scheme. I am not yeat convinced it is the best of methods, but for smaller volume oscillators it is certainly an interesting approach. Cheers, Magnus _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
