[time-nuts] Fury Interface Board: 5MHz needed?

[Magnus Danielson]

From: xaos <xaos at darksmile.net>
Subject: Re: [time-nuts] Fury Interface Board: 5MHz needed?
Date: Sun, 04 Nov 2007 10:24:59 -0500
Message-ID: <472DE44B.7050407 at darksmile.net>

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> Errors-To: time-nuts-bounces+magnus=rubidium.dyndns.org at febo.com RETRY
> 
> Hello everyone,
> 
> Shall we consider 5MHz OCXO's?
> 
> I have a BUNCH of those. Most are really low end devices but I also have 
> a few gems.
> I mean, some people might have a really nice 5MHz OCXO. Why exclude 
> them, if we don't have to?
> 
> Anyone out there with interest in this?
> 
> If nobody, except me, wants this I'll just drop it.
> 
> Bruce suggested that a NIST JFET frequency doubler might do the trick.

It is a very good and simpel solution.

> What does the math say?
> 
> If the frequency is multiplied by two, what else is multiplied?
> Frequency error? I would think so.

The normalized frequency error does not change, just the relative error.
Remember, you divide with the nominal frequency.

> What about phase noise?

Doubles from the source and some addition. However, you normally have a very
stable and good oscillator at 5 MHz.

It is slightly less optimal, but using a good doubler like the NIST JFET one
makes it reasnoble.

I think it should be manageable. Im with Bruce on this one.

Cheers,
Magnus