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

[Bruce Griffiths]

John Ackermann N8UR wrote:
> 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
>   
John

Why not lock it to a GPS timing receiver output when its at home, and
allow the controller to learn the aging and tempco characteristics etc
of the oscillator being disciplined and use this information to correct
for temperature variations etc at the remote site?

The model used can be as complex as required to achieve the desired
performance and a PC can be used to derive optimum correction
coefficients, the micro only has to perform the simpler task of applying
these corrections.

Bruce