How to send more than one data(bit wise,serial ex:1001,1010 etc) in infrared transmission with same frequency?

Question

is it possible using multivibrator circuits? if not possible with same frequency can i modulate and send it?

Answer 1

The standard method is to modulate the power to the infared transmitter (diode, laser, etc).  "1" represents power on and light present.  "0" represents power off and no light present.

An interface circuit to convert the serial bit stream logic level input to the power controller is needed.  An IGBT in series with the power of the diode/laser (source and drain), with the serial bit-stream applied to the base terminal of the IGBT is the simplest method.

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