[time-nuts] Crystal ovens
jmfranke at cox.net
Wed Jun 10 18:03:13 EDT 2009
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
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.
More information about the time-nuts