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ISSUE 1; February 2016
Description
A GPS disciplined OCXO incorporating GPS receiver unit, to
give 1PPS and 10MHz output.
Holdover stability up to 1.5µs over 24hours, achieved using an
adaptive algorithm.
Standard NMEA0183 data is available to the user via serial
port.
Frequency stability better than 1E-12
Working States (Reference Drawing): Run1: Fast track. Adjust the OCXO 10MHz output frequency quickly to track the GPS. Run2: Slow track. Adjust the OCXO 10MHz output frequency slowly when phase error is in the defined range. Holdover: No GPS input present; an algorithm enables adaptive modelling of the frequency stability of an OCXO with reference to the GPS timing signal. Free Run: Clock module powered up with no GPS input.