[ntp:questions] Slow convergence of NTP with GPS/PPS

David Woolley david at ex.djwhome.demon.co.uk.invalid
Tue Oct 21 20:43:28 UTC 2008

Unruh wrote:

> The "way better oscillators" I think is primarily oscillators which are
> temp controlled (yes heaters) and selected/adjusted.
Nowadays they are as likely to be TCXO's, temperature compensated 
crystal oscillators, in which the temperature is measured and used to 
drive a varicap diode, across the crystal, to compensate.  I think 
portable GPS receivers tend to use that approach.

In principle, you can also apply that compensation in software; you just 
need access to a thermistor that is thermally bonded to the crystal.

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