[time-nuts] Supply voltages for the Efratom 105243 10MHz OCXO

Greg Broburg semiflex at comcast.net
Sun Mar 20 16:35:09 UTC 2011


I will cast a vote on this one.

Set it up and try it.

Remember that a part of the feedback loop is the
thermal path out of the can and that the unit is offered
to work over a wide temperature range.

Worst case, if the loop works correctly at 20V but
does not make the mark that it did at 24V (start the
test at 24V with 72 hours for stability) blow air on the
can and observe for 72 hours.

Now drop the Voltage to 20 and observe for 72 hours.
Blow air on the can and observe for 72 hours. If it moves
more than the 24 V tests showed then add some insulation
around the cover to reduce thermal loss.

My guess is that it will work fine at room temp maybe
wider too.

Regards;

Greg




On 3/20/2011 9:15 AM, Bob Camp wrote:
> Hi
>
> It's tough to know just how far off of 24 V they compensated the oven. It's unlikely that they have a pre-regulaor on the heater. As you drop the voltage, the oven gain will also decrease. It's safe to bet that it will work at 24 +/- 10%. Past that - who knows... At 20% low, the failure is unlikely to be catastrophic. The impact will simply be a degradation in the temperature stability.
>
> Bob
>
>
> On Mar 20, 2011, at 4:24 AM, Mike Millen wrote:
>
>> Many thanks to both of you.
>>
>> Is it safe to assume that the oven has its own temperature control system?
>> I ask, because I'd prefer to run it from  approx. 20v instead of 24v.
>>
>> With a controller (&  a room-temperature environment) I'm hoping that it would still be
>> operating at its design temperature with a lower voltage.
>>
>> Comments?
>>
>> Mike




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