[time-nuts] Morion MV89A position

[Charles Steinmetz]

Dave wrote:

>what about replacing your aluminium box with a, say 2 foot piece 
>of  6 inch pvc pipe (ocxo suspended inside it clear of the wall and 
>sealed off ends) and burying that a few feet in the ground?

I share Poul-Henning's lack of enthusiasm for burying 
electronics.  But if you try it, I'd be interested in hearing how it 
works.  Depending on your climate, you may need to go deeper than a 
few feet to achieve a reasonable approximation to isothermy.  Of 
course, even a few feet should get you to where the rate of change of 
temperature is quite slow and the peak-to-peak swing is lower than 
the outside air temperature.  (But is that the standard?  Aren't most 
time-nuts labs in climate-controlled living spaces?).

If you really want to go nuts, it's pretty simple to put the cast 
aluminum box into a larger enclosure with a small, thermostatically 
controlled fan.  If you bond a temperature sensor to the inside wall 
of the cast box, it's easy to hold the temperature of the cast box to 
well within 0.1C.

Best regards,

Charles