CD4001 composed of single-channel modulator
Posted on Dec 11, 2010 11601
Core elements of this circuit is the second four-input NOR gate terminal IC CD4001, the entire circuit is simple structure, less components, easy to make, especially for remote
control transmitter or a carrier modulation transmission. As shown in the specific circuit-channel remote control transmitter modulator NOR gate IC1-1, IC1-2 composition multivibrator, the oscillation frequency is 40kHz. On input NOR gate IC1-1 for control terminal, when it is high, the circuit stop vibration; when it is low, start-up circuit. Switch Sl to the control button when Sl is pressed, the input terminal of the NOR gate IC1-1 is low, the oscillator circuit to work, the output 40kHz, 50% duty cycle of continuous square wave. Change in resistance or capacitance Cl R3 can change the oscillation frequency of the circuit. NOR gate ICl-3, ICl-4 composition of the buffer stage for improving circuit drive capability. The modulator output signal sent to the subsequent transmission circuit.