[GPS_Standard] Re: "Control of Rubidium Standard" by Stig

[Richard Moore]

Stig, there's enough gain in the DAC amplifier system to deliver the  
control, but I don't think this will be successful. Over the last 22  
hours, for example, my implementation of Bert's standard, which is  
controlling an HP 10811 VCOCXO, shows a wandering variation of the  
average frequency offset (collected over 7178 total samples, using an  
averaging period of 225 samples=1 hour) of -3.6E-9. The control is  
going to have to be far finer than this for your use.

I am forming the opinion that an averaging system built on computing  
a running average of a large number of samples, with a DAC update  
based on the running average and applied after each sample, might  
provide better stability and tracking. I don't know if this would be  
possible using the current PIC chip that Bert employs. I would be  
very interested in the opinions of others.

Best,
Dick Moore


On Aug 19, 2008, at 1:01 AM, gps_standard-request at mailman.qth.net wrote:

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> Today's Topics:
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>    1. Using the VE2ZAZ Controler with an Robidiun Stadard	??
>       (Stig Kristiansen - OZ3XO.)
>
>
> ----------------------------------------------------------------------
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> Message: 1
> Date: Mon, 18 Aug 2008 20:42:40 +0200
> From: "Stig Kristiansen - OZ3XO." <oz3xo at e-box.dk>
> Subject: [GPS_Standard] Using the VE2ZAZ Controler with an Robidiun
> 	Stadard	??
> To: <gps_standard at mailman.qth.net>
> Message-ID: <5FEA659E01A44704A2659FAD24588582 at 3XO>
> Content-Type: text/plain;	charset="iso-8859-1"
>
> Hi All.
>
> I am new to this Group, and my name is Stig - OZ3XO, and I am a  
> Professionel Radio Technician, working with Satellite Communication.
> I have Purges a Robidium Standard, that I am Planing to be  
> COntroled by the VE2ZAZ Controler.
> Dos anyone having a knolega if the Controler has a Problem with  
> Controling the Robidium, as having a very Narrow Tuning Range, of  
> only +/-1,5E-9 @ 0-5V-dc, ( 0,03 Hz @ 10 MHz ).
> Will this work at all, or are there any user Parametres that i have  
> to set up a Special way ??
>
> Stig - OZ3XO
>
>
>
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> End of GPS_Standard Digest, Vol 22, Issue 2
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