No subject

cycle spike are BOTH caused by an outside source,
such as your Heater cycling, maybe by way of the power supply etc.
It does Not have to mean the 0.01 deg is causing the problem.
If you can measure it, then it just means there is still room for 
improvement,
and that your Temp control and Tbolt setup may not be perfect yet.

ws

*****************
----- Original Message ----- 
From: "Mark Sims" <holrum at hotmail.com>
To: <time-nuts at febo.com>
Sent: Monday, December 28, 2009 8:20 AM
Subject: [time-nuts] Thunderbolt oscillator temperature sensitivity



Ever wonder if a +/- .01C temperature cycle would have any measurable effect 
on the Thunderbolt oscillator?   Well,  wonder no more...

Attached is a plot (in red) of the fast Fourier transform of the Tbolt 
oscillator data.  The temperature was cycling +/- .01C with a period of 
635.6 seconds.  That big red spike in the FFT data (just under the ':' in 
the Filter: in the plot) is also at 635.6 seconds.

Ignore the OSC tempco value shown since that measurement needs to be done 
with the oscillator undisciplined and the temperature moving...  the true 
value is around 1/10th that.