> May be beam sensors are the way to go...
I read an article on making your own beam 'break' detector recently where
it worked on a reflection basis just like the hand dryers in toilets. I
don't remember the range it worked over but it was adjustable. Just another
option? It would mean just one unit not two as a conventional beam break
and may be easier to isolate from the effects of sunlight.
Ian
Comments to the Webmaster are always welcomed, please use
this contact form
. Note that as this site is a mailing list archive, the Webmaster has no control
over the contents of the messages. Comments about message content should be directed
to the relevant mailing list.