A touch switch is a switch that is turned on and off by touching a wire contact, instead of flicking a lever like a regular switch. Touch switches have no mechanical parts to wear out, so they last a lot longer than regular switches. Touch switches can be used in places where regular switches would not last, such as wet or very dusty areas.
Parts:
C1__________10uf 16V Electrolytic Capacitor
R1,R2_______100K 1/4 Watt Resistor
R3__________10 Meg 1/4 Watt Resistor
U1__________4011 CMOS NAND Gate IC
MISC________Board, Wire, Socket For U1
1. The contacts an be made with just two loops of wire close together, or two squares etched close together on a PC board.
2. When activated, the output of the circuit goes high for about one second. This pulse can be used to drive a relay, transistor, other logic, etc.
3. You can vary the length of the output pulse by using a smaller or larger capacitor for C1.