[Milsurplus] BC-221Tempature compensating Capacitors Last call.

[John Hutchins]

All -
Charted the Crystal  oscillator circuit change in frequency  V.S. change 
in temperature deg Centigrade  is 0.002739 Khz/Deg C  The frequency 
drifts lower with higher heat.  Around 95 Deg F it hits 1000.000.  The 
Grid circuit has a 1Meg resistor, with Ceramic Capacitor at 6pF, with  
1.8pF 12pF Air trimmer all connected in parallel across the 1000Khz 
Crystal feeding the Grid and tied to ground.  Note the Air trimmer 
plates are about 1/3 engaged.
 
Is there a way to convert observed frequency change to C?pF PPM/Per Deg 
C  to get a ball park temperature compensation figure?

Thanks
Hutch