Posted on Apr 27, 2012

This simple IR detector turns on a real LED when Q2 is exposed to invisible IR radiation found in fiber-optics systems, position sensors, and TV remote-control units. The device can be built on top of a 9V battery and held in place with RTV. Its power dissipation is virtually zero, unless IR radiation or high ambient light is present. Normal fluorescent lighting is not a problem, but if necessary add an IR filter to the Q2 detector to exclude ambient light.

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

Exposing the detector to a strong light or IR source gives a quick check of the battery and the red LED.

Leave Comment

characters left:

New Circuits



Popular Circuits

Jfet bipolar cascode video amplifier
20A Transformerless Power Supply Schematic Diagram
Servo4 Module
Door Bell Circuit Using BEL 188 PCB
Simple PWM inverter circuit diagram using PWM chip SG3524
Weller WLC100 Electronic Soldering Station Circuit Q4012LPH
Replacing Motorola Batteries
Astable multivibrator in an 8 pin PIC
1930 ~ 1990MHz narrow-band RF2320 linear amplification circuit diagram
Cooling fan control socket synchronous circuit diagram
Capacitive load drive circuit diagram of the MAX4106 4107