http://www.dse.com.au/cgi-bin/dse.st...uct/View/K2807
this is possibly the closest i've seen on the net to what i'd be looking for, with a bit of fiddling, i reckon it could provide what is needed, the only thing to add to it would be some kind of counter. so after say 10 (variable, of course) cycles, it's turned off, or somesuch.