An Infra Red wired Repeater circuit to control appliances from a remote location. Parts List: R1: 1k Resistor (1) R2: 3.3k Resistor (1) R3: 10k Resistor (1) R4: 15k Resistor (1) R5: 2k2 Resistor (1) R6: 470R Resistor (1) R7: 47R Resistor (1) 0.5 Watt PR1: 4.7k Preset (1) C1,C3: 47u Elect(2) C2: 1n Polyester 5% or better (1) C4: 100u Elect(1) Z1: 5V1 Zener (1) Q1: BC549C or BC109C or 2N2222 (1) Q2: BC337 or BC549 or ZTX450 (1) IC1 : TSOP1738 IC2: 555 or 7555 (1) LED1 5mm RED (1) LED2,3 IR diode TIL38 or similar (2) Alternatives to IC1 : Everlight IR receiver module ELIRM 8621 Harrison electronics IR1 Vishay TSOP 1838 Radio Shack 276-0137 Sony SBX 1620-12 Sharp GP1U271R Notes: The signal emitted by an IR remote control contains two parts, the control pulses and a modulated carrier wave. The control pulses are used to modulate the carrier, a popular modulation frequency being 36 and 42KHz. The signal is radiated by an IR diode, typical wavelengths in the 850 and 950 nm region of the elect...