Parts List:
R1 10k
R2 1k
R3 33R 1W
R4 3k3
Q1 BC109C
IC1 LM7805
IC2 CMOS 4049B
IC3 IR1 module from Harrison Electronics See Last paragraph
LED1 Red LED (or any visible colour)
LED2 TIL38 or part YH70M from Maplin Electronics
C1 100u 10V
C2 100n polyester
The IR1 (IC3) module operates at 5 volts DC. This is provided by the 7805 voltage regulator, IC1. Below is inactive (no), the voltage on the conditions of the filter to 5 volt DC output. This should be reversed and the transmitter photo infrared LED, LED2 lead to be buffered. The buffer is provided by a door (pins 2 and 3) IC2-4049 CMOS hex inverter. The module can directly fly logical IR1 TTL, but pull up resistance, R4 is required for CMOS IC interface. This strength will ensure that the signal will change from a remote control from 0 to 5 volts. TTL logic levels are slightly different CMOS, 3 3 k R4 resistance to ensure the supply of + 5 V 5 logical high voltage signal line, not the wireframe TTL-3, 3 - volt level. The resistance has no effect on the performance of the IR module, but ensures that the module correctly is the CMOS buffer without instability training.
The output of the 4049 pin two discs directly transistor Q1, resistance R1 10 k limiting current base. LED1 is a red LED flashes to indicate that when a signal is received from a remote control. Note that in this circuit, the carrier is always present, but at reduced levels, and the decoded IR signal. The 4049 CMOS and transistor BC109C amplify the signal and LED2 conduct with a peak current of about 120 mA when a signal is received. If you try with a measure of digital meters, it is much less likely to read/30mA, as numerator, the average for DC, not be measuring the peak current. All devices designed to work 36 to 40 kHz should have reduced the controls with carrier frequencies outside this range, but should work. The exception is that some satellite receivers have IR commands to use a modulated more carrier assignment of approximately 115 kHz. Currently make this book is not with my connection, but I am working on a version of Mark 3 of the carrier.
The main difference between this version and the previous circuit, it is that this design uses an available infrared module. This module is IR1 of Harrison Electronics part number in the layout of the United Kingdom. The IR module contains an integrated photodiode amplifier and buffer circuit and the decoder. It is on the commune centerd use 38 kHz carrier frequency that controls most of the IR. The module removes most of the carriers allows decoded transmitted pulses to the application. Domestic TV and VCR use additional filtering is used to remove the door completely.
The IR1 of Harrison Electronics part number is no longer available. They provide an alternative IR decoder I've tested and work. Other infrared decoders alternatives are presented below, but note that do not all share the same pinout. I advise anyone to check this in the corresponding sheet.
Vishay TSOP 1738
Vishay TSOP 1838
Radio Shack 276-0137
Sony SBX 1620-1612
High GP1U271R
