[time-nuts] (no subject)
Charles Steinmetz
csteinmetz at yandex.com
Sun Jan 25 14:53:32 EST 2015
>Typically a PLL loop uses a PI loop-filter, making it a PI-control
>system with a steered integrator in the form of the oscillator. Many
>other control systems prefer to use the PID controller
I have seen no evidence that the Thunderbolt, in particular, uses a D
term. Nor have I seen any evidence that it steps the PLL loop
parameters during startup. It *is* capable of "jam setting" the
oscillator phase (allowing cycle slips to reset the phase error
within +/- 50 nS), which can speed up the lock time considerably. I
thought it was supposed to do this automatically if you turn jam
setting ON and set a phase error limit, but I have never seen one jam
the phase without sending it a manual jam command, even with jamming
ON and a phase error limit set.
If anyone has managed to get a Tbolt to jam the oscillator phase
automatically on startup, I'd be interested to know how.
Best regards,
Charles
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