how can you make a cheap pressure switch that will complete the circuit when opened?

like in a talking post card but custom record able.

frollard8 years ago
the circuit used in 'talking' gift cards is really simple the blue tab with hole in it slides in and out (as the card opens and closes) the yellow is the contact plates, tinfoil glued to paper, or if you have it copper tape etc. The black is the paper, and the thin black on top is tape to hold it down. Note how the top piece has a bump in it, so when the blue is pulled out a bit, the hole seperates the plates, but when you pull the blue out, it closes the circuit.
also - the top half is top view, bottom half is side view.