[time-nuts] need recomendation for a portable 10mhz reference oscilator

[Alan Melia]

Hi John, Andy Talbot G4JNT developed the a Jupiter based GPSDO for just this
purpose, several are used by hill-toppers in the UK.
http://www.scrbg.org/g4jnt/freqlock.htm
The idea was that it would settle and be accurate in the time it took to
seet up the microwave part of the station.

I hope that helps/
Alan G3NYK

----- Original Message -----
From: "John Ackermann N8UR" <jra at febo.com>
To: "Discussion of precise time and frequency measurement"
<time-nuts at febo.com>
Sent: Tuesday, December 11, 2007 8:56 PM
Subject: Re: [time-nuts] need recomendation for a portable 10mhz reference
oscilator


> Hal Murray wrote:
> > I'm picturing an open hill top at night with clear skies so there would
be
> > lots of radiation cooling.  Of course, with an open hill top, GPS
recption
> > would be easy.
>
> As great as GPSDO are, the problem with using them in a portable
> environment is the time it takes to do a survey and then get to final
> lock; mountain-toppers may not be in one place long enough.
>
> One thought I've had is to use a cheap Rubidium for long term stability,
> and phase lock a good OCXO to it for short term stability and phase
> noise (ie, use a loop time constant of perhaps 100 seconds).  That would
> make a portable package that would meet both the short and long term
> stability requirements.
>
> John
>
> _______________________________________________
> time-nuts mailing list -- time-nuts at febo.com
> To unsubscribe, go to
https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
> and follow the instructions there.