Capacitive Sensor(Touch switch relay) with BC337

Special design for shop-windows animation
Useful for many types of touch controls

The purpose of this circuit is to animate shop-windows by means of a capacitive sensor placed behind a post-card-like banner. The card is placed against the glass inside the shop-window, and the visitor can activate the relay placing his hand on the card, from the outside. Especially suited for toy-shops, the circuit can activate model trains, small electric racing cars, lights etc. Further applications are left at user’s imagination. Adopt it to increase the impact of your shop-window on next Christmas season!

Parts:
R1,R2_____1M 1/4W Resistors
R3,R4____47K 1/4W Resistors
C1_______10µF 25V Electrolytic Capacitor
C2______470pF 630V Ceramic or Polyester Capacitor
D1-D3____1N4002 100V 1A Diodes
Q1-Q3_____BC337 45V 800mA NPN Transistors
RL1_______Relay with SPDT 2A @ 220V switch
Coil Voltage 12V. Coil resistance 200-300 Ohm
J1________Two ways output socket
Sensor____Aluminium or copper thin sheet with the dimensions of a post-card,
glued at the rear of the same (about 15×10.5 cm.)
Thin screened cable

Please read more at the original source: http://www.redcircuits.com//Page22.htm
Thank you.

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