[time-nuts] Temperature controlled TCVCXO

[David]

Just to be clear here, my original question referred to using a TEC to
maintain a constant temperature where the TCVCXO with the crystal has
the best stability.  I assume this would be around 25C but testing
might reveal that it is actually more stable at a point slightly
higher or lower.

So the TCXO would be operating at or around a fixed point near 25C
whether the ambient temperature is higher or lower.  Bidirectional
control of the TEC with a servo amplifier is not difficult and that
second HP link is pretty close to what I had in mind.

On Fri, 13 May 2016 16:30:20 -0700, you wrote:

>Hi Nathan,
>
>Let me state what Bob is driving at in a different way.
>
>Your biggest problem with a TCXO is the crystal.  It is cut so that the 
>slope, relative to temperature, has the shallowest curve around room 
>temperature (between 20 to 25 degrees C).  If you cool or heat it from 
>that range the slope becomes more radical.  The more radical the slope 
>the greater the change in frequency for a given change in temperature.  
>The exact opposite of what is trying to be achieved.
>
>This translates into having to have an extremely tightly controlled oven 
>system in an attempt to overcome the radical slope.  In addition you 
>will also have to consider the elevated temperature effects on the other 
>components.  It is a never ending battle.
>
>Bill....WB6BNQ