Dividing circuits

I am building a free pendulum clock, and am hoping to get pulses at the rate of one per second from a photoelectric cell in the path of the pendulum. Where can I find a circuit which will count these, and give out a signal after 30 pulses? This would be used to drive the clock hands, and also power a magnet to keep the pendulum swinging. Thanks for any help, John

there's a milion different ways to do that... a small microcontroller could be programmed to emit a pulse evert 30 clock cycles, or you could build a divider from discrete logic... (eg a couple of decadee counters in series the first wired as divide by 3 the second as divide by 10) or set up a 29.5 second monostable triggered by the pendulum - every thirty seconds the pendulum will re-synchronise it.

Bye. Jasen