infrared remote control switch

Infrared Remote Control Switch

  Now a day, everyone wants to control their appliance wirelessly (i.e. remote control). Here is a simple tested and inexpensive remote control switch utilizing reading available components

  As in all wireless systems Infrared (IR) remote control switch also comprise two major section i.e. transmitter and receiver section.

  Transmitter Section: – The logic of this section is simple and is build around most versatile IC NE555 (IC1), configured as astable multivibrator to produce frequency about 38 KHz. This is so, because IR module receiver used here works in range of 38 KHz frequency. Timing component of infrared remote control switch is resistor R1 and R2 and capacitor C2, determine the range of oscillating. Where, formula of generated frequency (F) from transmitter section IR remote is given by

  F = 1.443 / (R1 + 2R2) C2

  The output frequency from pin 3 of IC1 is fed to base of transistor T1 through resistor R4 and is configured as Darlington pair with transistor T2 in order to drive IR LED and resistor R5 works as current limiter.

  Receiver Section: – Transmitted signal from transmitter is received by infrared (IR) receiver module (TSOP 1738) and is fed to base of PNP transistor T3 through resistor R6 for amplification. Amplified signal is fed to pin 2 of IC2 through coupling capacitor C6. IC2 is configured as monostable multivibrator which is triggered when low pulse from receiver module is given and its output goes high only for 5 second.

  The output from IC2 is given to pin 14 of decade counter IC (IC3) through resistor R12. Here two outputs (pin 2 and 3) is taken from IC3 which alternately go high for every clock pulse. Initially at starting time (when no signal is received) pin 3 goes high and no gate current pulse is received by TRIAC1. But when signal is received pin 2 goes high and activate TRIAC1, which, in turn controls the appliance.

  NOTE: – Glowing LED1, LED2, LED3 and LED4 is used to indicate signal transmission, presence of power supply in receiver section, signal received and appliance off respectively.

Parts List

Resistors (all ¼-watt, ± 5% Carbon)

R1 = 8.2 KΩ

R2 = 15 KΩ

R3, R8, R11, R12, R13, R15 = 1 KΩ

R4, R14 = 470 Ω

R5 = 10 Ω

R6 = 680 Ω

R7 = 5 KΩ

R9 = 10 KΩ

R10 = 220 KΩ

Capacitors

C1 = 100 µF/25V

C2 = 0.001 µF

C3, C8 = 0.01 µF

C4, C9 = 100 µF/16V

C5, C6 = 10 µF/16V

C7 = 22 µF/16V

Semiconductors

IC1, IC2 = NE555

IC3 = CD4017

IC4 = LM7806

TRIAC1 = BT136

T1, T2 = BC547 (NPN)

T3 = BC558 (PNP)

ZD1 = 5.1 V zener diode

IRX1 = TSOP 1738 (IR receiver module)

Miscellaneous

SW1 = push to on / off switch

LED1 = Green

LED2 = RED

LED3 = Yellow

LED4 = white