[time-nuts] Thermal insulation choice?

[Charles P. Steinmetz]

Rick wrote:

>We also tried mounting the modified 10811 in Hammond metal box.
>Initially, we mounted the 10811 to the box using the
>two standoffs that come with the 10811.  However, this
>degraded the performance somewhat.  We removed these and
>had the 10811 supported mechanically only by the edge
>connector.  With that change, it was as good as the cardboard
>box.

I often mount OCXOs inside metal boxes with nylon or teflon standoffs 
(or resilient mounts, for some vibration isolation), with excellent 
results.  If tighter temperature control is needed (IME, it often is 
not), mount that box inside another box on thermally insulating 
standoffs and control the air temperature in the larger box with a 
thermostatically-controlled fan.  (The control should be set to no 
more than the maximum expected ambient temperature, or perhaps a bit 
lower, to preserve as much thermal differential for the oscillator 
oven as possible.)

Best regards,

Charles