This infrared transmitter use PWM (pulse width modulation). The transmitter is equiped with LM567, tone decoder circuit. Audio signal ( at least 50mVvv ) is amplified with T1 and then it is used to ...

Using this circuit, audio musical notes can be generated and heard up to a distance of 10 metres. The circuit can be divided into two parts: IR music transmitter and receiver. The IR music transmitter ...

This Infrared transmitter can activate IR based switching circuits from a distance of 10 meters or more. It is a high power IR transmitter driving two IR LEDs through a Darlington transistor BD 139 to ...