The device is intended to control a satellite tuner from another room. This issue occurs when the tuner is on and one of the two or more TVs in different rooms.
The receiving part is left near satellite tuner, directing the led in the window the infrared receiver and transmitter with remote control off to another room where the TV is.
The transmitter is controlled by an IR receiver in industrial production TSOP type with built-in carrier demodulator ( 36 kHz) . When the transmission is used 100% AM .That is, if 1 ( carrier is ) if 0 ( no carrier and the transmitter is turned off ). The final stage of the transmitter is slightly open in a silent current of 15 mA. The antenna of receiver and transmitter - quarter-wave pigtails ( 16 cm ).
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Receiver - the superregenerator with very good repeatability ( produced 3 copies of devices with absolutely no problems at the frequency of 433.92 MHz and 418 MHz SMD components ) and excellent sensitivity. Its setting is reduced to the selection of the capacitance between the collector and emitterom of the transistor and the capacitance and inductance of the oscillatory circuit and the coil connection to the antenna. To monitor the signal received by the receiver with the release of the first OS ( 1 leg LM 358 ) plugging back the control input of the ULF . The second AW is part of the chip - threshold device , with him on the timer is a digital signal. The timer restores the arrival of high-level carrier frequency 36 kHz and controls the transistor that fires the IR led.
Author: Sergey, Kremenchug, This email address is being protected from spambots. You must have JavaScript enabled to view it. ; Publication: www.cxem.net