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.
| Part | Total Qty. | Description | Substitutions | | C1 | 1 | 10uF 16V Electrolytic Capacitor | | | R1, R2 | 2 | 100K 1/4 Watt Resistor | | | R3 | 1 | 10 Meg 1/4 Watt Resistor | | | U1 | 1 | 4011 CMOS NAND Gate IC | | | MISC | 1 | Board, Wire, Socket For U1 | |
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- The contacts an be made with just two loops of wire close together, or two squares etched close together on a PC board.
- 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.
- You can vary the length of the output pulse by using a smaller or larger capacitor for C1.
