Circuit electrinic

Here is a tester for on-board testing of IR receiver modules used for remote control of TV sets and VCD players. The circuit is very simple and can also function as a remote tester. IR receiver modules are miniature IR receivers sensitive to pulsed infrared rays. These have a pin photo-diode and a preamplifier stage encased in an epoxy case that acts as the IR filter.

Infrared (IR) Receiver Module Tester Circuit Diagram

Internally, the module has an AGC, band-pass filter, demodulator and control circuit. Its output has a bipolar transistor with 80- to 100-kilo-ohm resistor in the collector. Normally, the collector output of the transistor is high and gives 5V at 5 mA. The output of the module is active-low and hence it sinks current when the pin photo-diode senses the presence of pulsed IR rays.


The IR receiver module is designed with high immunity against ambient light and is capable of continuous data transmission at up to 2400 bps or higher. The band-pass filter and AGC suppress unexpected noise to avoid false triggering. The module responds to the IR beam only if its carrier frequency is close to the centre frequency of the band pass.

IR Receiver Module Pinout

Working of the circuit is simple. Three mini crocodile clips are used to connect the circuit to the positive, negative and output of the module. If the module is properly working, its output remains 5 volts. This makes the cathode of LED1 high. So LED1 doesn’t glow and the buzzer remains silent. When you focus the remote handset onto the IR receiver and press any switch, the output of the IR receiver sinks current.

So LED1 starts flashing and the buzzer beeps in sync with the pulsations of the IR beam. On the other hand, if your IR receiver module is faulty, the output of the module does not sink current when you focus the remote handset towards the module and press any switch. So neither LED1 flashes, nor the buzzer beeps in sync with the pulsations of the IR beam.

Power to the circuit is obtained from a 9V PP3 battery and regulated to 5 volts by zener diode ZD1. Most of the IR receiver modules work only between 3 and 6 volts. Storage capacitor C1 releases current to make LED1 flash brightly. (EFY Note. We had used a TSOP1738 IR receiver module while testing. Fig. 2 shows the pin configuration of TSOP1738.)

Assemble the circuit on a small piece of matrix board and enclose in a small cabinet. Use a high-brightness red LED and a small buzzer for audio-visual indication. Connect points A, B and C to the crocodile clips using red, black and blue wires to connect to the pins of the module easily. For easy identification of pins, the pin assignment (front view) of some common IR receiver modules is shown in the table.

This is Infrared Remote control transmitter circuit has high performance and can be applied to works with the various infrared receiver circuit. To made easily. And best to save your money.
I need not tell you much, what is the infra red remote control. Because you have known as well. so I recommend circuits 2 types, as appropriate.
- The first is simple circuits. Infrared light from a set to a set to work immediately.
- Then another circuits, is designed to have wider applications. Can be set program that will be must have a beam of infrared light to circuits few times to work.
Which both need to have the good Infrared Remote control circuit, before.
The infrared remote control transmitter circuit.
Usually, when input voltage to the infrared diode. Will be have the beam infrared light which can be seen with the naked eye out
-But in real applications. We need to enter the signal pulse with a frequency of about 5kHz, to the infrared diode, for eliminate the various interference. And reduce the power supplied to the diode.
In the first circuits, to be a simple infrared transmitter with IC-555 timer to an oscillator generator at frequency of 5kHz, that is set with R1,R2 and C2. The output signal will have signal period on-off 1:1
The resistor R3 is used to limit current flow through the infra red diode under 50mA.

If you want the infrared transmitter that has the signal strength is very high. You can be done by adding the output transistors. Enable With the infrared diodes up to three tubes.

Be seen from the circuit, IC 555 use to function frequency generator is 5000Hz as well. The frequency of the circuit is determined by the VR1, R1, R2 and C1, we can customize the frequency by adjusting VR1.
Output of IC is supplied to the transistor Q1-BD137 to drive infrared diodes with high current to 100mA. Risisetars R3 in the circuit should not be less than 3.9 ohm as it may cause damage to TR1. R4 and LED1 to indicate that the voltage supply to the circuits.

Infrared transmitters by LM3909

This is an infrared transmitters signal circuit that is small size and using a power supply 1.5V only. by main electronic part are two the LM3909 (a LED Flasher Oscillator IC) Normally, we tend to put it to use as a simple flashing light circuit. Using a 1.5V low power supply, it’s working now, Easier to use transistors. The high frequency, it is very simple, just change the device to high frequency only. C1 and R1 is lower the higher frequency.