IR Transmitter Tester. Application Circuit 4

ir-transmitter-circuitWe make Infrared Transmitter circuits to generate Pulsed Infrared rays to use with IR Sensor based receivers. The IR Transmitter circuit based on IC 555 generates IR rays pulsating in the frequency typically at 38KHz. The IR Sensor used in the receiver is TSOP 1738 which also works in the same frequency. So here is a simple IR Transmitter Tester to check whether the IR Transmitter is emitting 38 KHz frequency or not.
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Hacking a Remote. Application Circuit 3

remote-5We construct different types of Infrared Receiver LED ( Rx) or IR Sensor ( TSOP 1738 ) based circuits. To test, the working of the circuit we have to use an IR Transmitter. Usually we use IC 555 based IR transmitter for this. But the frequency of the IR from the Transmitter should match with that of the Sensor, otherwise the circuit will not respond. Here is a simple solution to test the IR based circuits. Simply Hack a Mini Remote obtained along with low cost FM radio, Toys etc. You have such Remotes in your Junk box. Let us Hack one such Remote to make a Tester.
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Pulsed IR Transmitter for Phototransistor. Sensor Circuits.6

Here is an Infrared transmitter circuit for emitting pulsed IR rays with a frequency of 4.5kHz for Phototransistor based receivers. The range of the IR transmission is around 1 meter. Unlike 555 IC based IR transmitters, it uses the Phase Locked Loop (PLL) IC as an oscillator. Phototransistors are more responsive to Pulsed IR rays than direct light.
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Design your Circuit. Part IV – IR Transmitter

Most of the consumer electronic devices use Infrared remote control for easy operation. The Carrier frequency of such remote control may be 36 kHz or 38 kHz. The Control codes are sent to the receiver of the device in Serial Format. This format is Modulated to the carrier frequency by the On / Off method. In the Remote, the IR signals are generated using an IR LED which emits Modulated IR rays. This part explains the details of IR transmission protocol and the design of IR Transmitter.

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Long range uPD6121 IR Transmitter

Here is a long range Digital IR transmitter. It is a precision IR transmitter suitable for TSOP 1738 IR receiver module. Unlike other IR transmitters, this circuit is highly reliable and gives fail proof operation.

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