[time-nuts] RE: phase locking Rb to GPS

Alberto di Bene dibene at usa.net
Sun Oct 23 15:30:06 UTC 2005


Richard H McCorkle wrote:

> [snip]
>     In interfacing an Isotemp mil spec version of the HP 10811B with a
> sensitivity of 9.7e-9/volt and a span of 4.85e-8 to the Shera controller
> even with  [snip]

Richard,
  do you perhaps have any experience of using the Isotemp OCXO134-12 unit ?
I built a GPSDO using it, and it works rather well, were it not for a 
residual oscillation of the frequency of about +- 2E-11. i.e. +- 0.0002Hz
at 10MHz, with an oscillation period of about 7 minutes, which is too fast
to be corrected by the PI software loop.

I attributed it, lacking other explanations, to an imperfect temperature
control of the oven. Translated in temperature terms, that frequency
oscillation amounts to a change of about 0.18 degrees Celsius.

What you think about this ?  TNX

73  Alberto  I2PHD

 





More information about the Time-nuts_lists.febo.com mailing list