Hi,
Hmm... most simple clock drive do the following:
1) a timing circuit to generate the clock signal (you need to know the EQ mount gear ratio),
2) a counter to convert the clock signal from the timing circuit to the correct clock signal for various sidereal speed if require,
3) a stepper motor controller will receive the clock signal and generate the correct stepper squence for the stepper motor driver.
Have a nice day.
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