Dividing circuits

Hello, John! You wrote on Fri, 09 Sep 2005 19:37:34 +1200:

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

I notice that Gay Macon has tried to hijack your most interesting thread buy crossposting it to the newsgroup where he is the moderator and spends a lot of time playing with himself, sometimes he gets lonely and does that sort of thing. Of course he might also see this as an opportunity for a bit of product development whereby he can impose his ideas about what he thinks you should be doing upon you.

I would like to point out that I am his boyfriend so don't even think about it.

I have crossposted your request to sci.electronics.design.

This is a newsgroup populated by a rational number of people (perhaps that should be a number of rational people) who are not and would not want to be Gay Macons boyfriend so I feel safe there.

They also know something about electronics and, if you leave them to it will have a massive stink of an argument about what they think you think they want. But you might get what you need from a free exchange of ideas.... indeed you might get some new ideas.

Having my own self serving agenda I'd be quite excited about doing the timing stuff totally electronically but using some form of motor control, in addition to the magnetic keep it going thing, to adjust the length of your pendulum and phase lock its movement to the reference crystal thing.

In fact..... to keep things a bit purer I'd do that but have some mechanical linkage off the pedulum to drive the metal bits that display the time.

Right, just off to have a wank now......

However SED is the place to be. GUY just wants to talk to himself but needs others for reassurance.

With best regards, Genome. E-mail: ilike snipped-for-privacy@yahoo.co.uk

Old London University exam question......

" A clock regulated by a seconds pendulum (ie, a pendulum whose period should be 2 seconds) loses 50 seconds per day. Find by what percentage the length should be altered in order that the clock should keep the correct time, and state whether it should be lengthened or shortened. "

Newsgroups cut to sed only.

Lengthen the pendulum by H, the distance from pendulum to the surface over which it swings. The percentage increase will be (L+H)/L The clock will keep (for 1 clock tick) correct time twice daily. Ed

Only if you include temperature compensating mercury vials in the bob.

;-) Rich