Posted on Jul 25, 2012

This touch-actuated switch stays on as long as you keep your finger on the touch plate. Rl sets the input impedance to a high 22 MO. Ql picks up stray signals coupled through your body to the touch plate and amplifies them to tum on Q2, which turns on lamp drivers Q3 and Q4. Lamp 11 is any small12-V lamp, such as a No. 53-12 V 120 mA. R4 and Cl add a small amount of hysteresis (delay) to keep the light from constantly flickering.

Click here to download the full size of the above Circuit.

A relay can be used for 11.

Leave Comment

characters left:

New Circuits



Popular Circuits

Stylus organ
Control motor PWM schematic
Low Frequency Sine wave Generators Schematic
magnetic switch circuit
phone hold circuit
simple optical switch
led thermometer pcb
Speed-Limit Alert
A typical computer motherboard CPU power supply circuit
Basic circuit diagram connection of signal and power ISO107
255W Valve RF Transmitter circuit