My talking communicators use a membrane keyboard of my design which I have had made for me. The keys are about 20mm square BUT each consists of an 11 x 11 array of "keylets" which are electrically joined. This keyboard uses "ink separator" technology to hold the membrane layers apart. The conductive part is a series of horizontal and vertical stripes at right angles to each other. A series of ink dots at the interstices of the x/y grid keeps them apart. IF your design can tolerate a custom keyboard this may be an acceptable way to go. The ink for the separators is a special one intended for this express purpose (from Canada I believe). Russell McMahon _____________________________ >From other worlds - www.easttimor.com www.sudan.com What can one man* do? Help the hungry at no cost to yourself! at http://www.thehungersite.com/ (* - or woman, child or internet enabled intelligent entity :-)) From: Mark Willis >Hi, all; I'm looking for some really small switches for a tiny >keyboard. > >Want to find some that're under 4mm square or so. SMD would be great, >for this. 2mm would be unbelievably great Something like "tactile >switches", as they're called. I'm starting to think I'll be doing >carbon conductive switches for this thing... > >I figure a nice SMD PIC on there would do for a keyboard monitor, if I >can find the switches. Otherwise I'll have to make some cobbled >together nightmare with stacked layers of switches and push-rods, ACK! > >I'm thinking of a way to use those 3mmx6xx rectangular switches with >pushrods if I have to, but other options would be far better.