Remote control circuit a composed of TDC1808

 The transmitting module TDC1808 can transmit non-FM signals, and can also be connected to an external modulation source to transmit modulated signals. The receiving module TDC1809 can
receive the high-frequency signal transmitted by TD01808 and has demodulation function. Its carrier frequency is between 250-300MHz, and there are about 10 frequencies
to choose from.
    (1) Transmitting circuit In the transmitting circuit shown in Figure a, the TDC1808 transmitting module is used. When S is pressed to turn on the 9V power supply,
the high-frequency oscillating signal generated by the oscillation circuit composed of VT1 and VT2 is sent to the transmitter through resistor R7. TDC1808 transmitting module, the transmitting circuit will transmit
the radio frequency signal modulated by square wave.
    (2) The receiving circuit is shown in Figure 18-34b. Press the switch S and turn on the 5V power supply. After the T DC 1809 receives the transmitted signal
and demodulates it, it outputs it from its l pin and sends it to the audio ship. The ◎ pin of the code clamor NE567 performs frequency decoding, and then the ⑧ pin of the NE567 outputs a low
level to control the work of the actuator.
    In order to meet the requirements of 9V and 5.1V for the transmitting circuit and receiving circuit, a three-terminal regulated and adjustable power supply is used in both transmitting and receiving circuits.
If necessary, dry batteries can be used for mobile use.