Talking Electronics

See Electronics for Model Railways Book 2!
A motor speed controller using Pulse Width Modulation. Output driven by a MOSFET.
A simple, high performance throttle, featuring a PWM FET output and a voltage controlled input.
The simplest version of the PWM throttle has two controls: speed and direction. Its even possible to remove the speed control pot altogether and use two push buttons in its place, one for accelerating and one for braking.
If computer control is what you are after, the throttle may be controlled either by a digital to analogue converter, or by selecting different voltage levels from a divider chain using 4051 analog multiplexer. In the second case, there will be only eight speeds available, but if the momentum circuit is used, it will smooth out the steps, making the transitions from one speed to the next undetectable.
Board dimensions: 2.1in x 1.9in.