At 09:30 AM 8/1/2012, Denny Esterline wrote: > > >I was going to suggest a DIY solution using either a Magnet/Hall/Reed >switch combination or, better yet, a photo slot interrupter. >Pivot a toggle/flag on a plastic axle between some felt washers and you >should be able to get the noise well below audible. I like the way you think. What I might be able to do is to=20 disassemble a standard mini-toggle switch and solder a metal flag=20 onto the lower end of the toggle, into the cavity where the switch=20 mechanism used to be. Add some felt material on either side of the=20 flag for friction, then use two slotted photo-interrupters to detect=20 end of travel. The two interrupters would then drive a S-R flip-flop=20 for clean switching with no problem of position ambiguity. This also has the advantage that I can use a standard 4000 series=20 CMOS part that works at the existing 12V supply rail. The existing switch is noisy because the announcer flips the toggle,=20 which then goes over-center and snaps into the opposite side. Its=20 that snapping sound that is causing the problem. If I go to a flag=20 with friction that has to be dragged into its new position, the=20 snapping noise is eliminated. I'll try it out over the next couple of days and let you know how I make ou= t. Thanks! dwayne --=20 Dwayne Reid Trinity Electronics Systems Ltd Edmonton, AB, CANADA (780) 489-3199 voice (780) 487-6397 fax www.trinity-electronics.com Custom Electronics Design and Manufacturing --=20 http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .