[time-nuts] Crystal ovens

[jmfranke]

There was an interesting paper by W. A. Morrison (made the first crystal 
controlled clock) in the July 1928 issue of Proceedings of The Institute of 
Radio Engineers, pages 976-980, entitled "Thermostat Design for Frequency 
Standards."
The article describes a crystal oven consisting of four layers: starting at 
the outer wall - a layer of insulation, a heater, a distributing layer, and 
an attenuating layer.  He described a case wherein the temperature variation 
is reduced by a factor of "at least 10,000 to one."

Of course this was for a passive crystal versus an active oscillator.

John  WA4WDL