DC motor PWM controller that takes the 1ms to 2ms pulse from the RC receiver and converts it into a pwm train at 1Khz. design is based around three parts.
… The controller board. This is a fully digital circuit that takes the 1ms to 2ms pulse from the receiver and converts it into a pwm train at 1Khz. It uses six cmos ics (74hc and 40 series) and a 4Mhz crystal clock. The only other components are one resistor and two capacitors to complete the crystal clock and a capacitor across the supply for smoothing. This was built on a printed board measuring 2 x 2.25 inches using standard components (on the boat there was no shortage of space). If surface mounted devices are used, the lot can be crammed into a much smaller space. The circuit can give a resolution of 128 steps (7bits). Some day I will expand it to have reverse function, but this is better done by a switcher circuit supplied from another channel (my reciever can give 7 channels and I am using only two at present).
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