Infrared transmitter and receiver for Wireless switch
Created: Sep 17, 2014
No description available.
Remote control system is not a new setup, in fact almost all appliances and devices are controlled through wireless transmission. This project is a simple transmitter and receiver concept using infrared to switch any device ON/OFF.
On the receiver’s side, the TSOP1740 IR (infrared) receiver is used to detect an infrared signal of 40kHz. TSOP1740 is a miniaturized receiver module for infrared remote control systems. This module produces an active-LOW output when it detects an infrared signal, thus the output is connected to the base of a PNP transistor BC557. The BC557 will not conduct when the TSOP1740’s output is passively HIGH (+5V), and switches ON when the TSOP1740 is trigger. An appliance or a device can then be incorporated on the output of the transistor. A relay switch must be added on AC-power controlled devices.
On the transmission’s side, two ICM7555 timers are used to vary the output frequency. The first ICM7555 produces a low frequency that will switch the BC107 ON/OFF, driving the second ICM7555 to produce a frequency that varies from 34kHz to 46kHz. One 555-timer can be used to produce a 40kHz frequency for ideal representation but it doesn’t work well on actual implementation. An IR LED (infrared light emitting diode) is then placed on the output for transmission.