[time-nuts] Regulating a pendulum clock
djl at montana.com
Sun Aug 8 22:28:52 UTC 2010
Hmmm lemme see. I think I'd use a 12 volt supply and two transistors
driven by two outputs on my Arduino,basic stamp,picaxe or other whizzie.
I'd then implement a PID controller essentially using the 1 sec pulse from
the pendulum and the 1 sec pulse from my Rb, satellite receiver, crystal
clock, or whatever. The appropriate output pin will be brought to ground,
and the other driven as a pdf with the rate given by the pid loop.
Temperature and even pressure corrections can be applied within the gizzie
software. External parts, minimum. Opportunity to play with tuning,
> J. Forster wrote:
>> You are picking very unimportant nits.
>> If there were a small noise spike from the opamp, it'd goose the
>> a tiny amount. That would be corrected on the next swing.
> Heuristic analysis of this type is counter productive.
>> You are turning a trip to the corner store into an Apollo Moon Mission.
> Reliability is paramount in a circuit that may be required to work for
>> BTW, since the =drive does not to be bipolar, one of the NPN and PNP
>> transistors can be deleted. They never turn on. So you are left with two
>> opamsa, =each with a simple emitter follower.
> The original request was for a bipolar drive.
> The lack of short circuit protection is poor design practice when
> driving an external load.
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