[Elecraft] 10 mHZ external reference VS the K3S's optional KTCXO3-1

[Edward R Cole]

Thanks, Ron, that is a better description of the EXREF function.

I left out the page number where the TCXO specs are given (in my 2010 
K3 manual) - page 8
It lists TCXO3-1 as 1ppm but I think it was commonly found to do 0.5ppm.

That matches my measurements at 28-MHz of 14-Hz error.  MY actual 
EXREF measurements showed better than 2-Hz accuracy which implies 
better than 0.1ppm.  It was something like 3-Hz at 50-MHz.

73, Ed - KL7UW

From: "Ron D'Eau Claire" <ron at cobi.biz>
To: <Elecraft at mailman.qth.net>, "'Doug Hensley'" <w5jv at hotmail.com>
Subject: Re: [Elecraft] 10 mHZ external reference VS the K3S's
         optional        KTCXO3-1
Message-ID: <001b01d11686$b02c5860$10850920$@biz>
Content-Type: text/plain;       charset="us-ascii"

 >From the K3EXREF manual Introduction:

The K3EXREF option locks the K3's reference oscillator frequency to an
external 10 MHz source by
automatically controlling the REF CAL function. While locked to the external
source, the K3's reference
oscillator frequency is maintained within 2 Hz. Since the K3EXREF does not
phase lock the K3's reference
oscillator, the external 10 MHz source has no impact on the K3's phase noise
performance. For best
performance we recommend your K3 be equipped with the KTCXO3-1 high
stability (0.5 ppm typ.) reference
oscillator.

73, Ron AC7AC


73, Ed - KL7UW
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