lagasse@biomed.UUCP (Robert C. Lagasse) (09/04/85)
Does anyone know of a mechanical (yes...mechanical) timer that I can
use as an alarm timout timer with contacts that can handle about 10A. Here's
the catch: The timing motor must be for 12V DC.
I want the kind that has a geared down motor that turns an adjustable cam
which eventually operates a microswitch after an adjustable delay of about
2-20 minutes. I have built long delays using 555s operating a relay and
have tried using other purely electronic means which are too glitch
sensitive and either reset occasionally by themselves or are destroyed by
high current transients in an automotive or building alarm environment.
It seems that every CMOS chip that I use lately decides to "internal
short" itself and load down the power supply as a low impedence........I am
considering throwing out all of my CMOS chips and going back to *VACUUM
TUBES*. At least *THEY* aren't afraid of real world transients.
Bob Lagasse