Sylvia Else wrote:
Don Klipstein wrote:

Cheaper still requires oscillators regulated by component tolerances
- and oscillators tend to have at least two components affecting
frequency, and finest tolerance of ones easily available at premium
prices is 1%, meaning low chance of achieving timing highly reliably
better than 2% in either direction unless either crystal or power line
time base is used.

I'd have thought getting the cycle to within 10% would be more than
adequate.

It would be. Washing machines used to use synchronous motors driving a
cam, which was far more accurate than necessary to do the job properly.

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W
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