[BrianG]

I was toying with making a similar device, but never went with it. The algorithm is pretty simple really, just take the pistol radio signal pulsewidth in ms, subtract 1ms, then multiple that by 2. Just use a floor value of 1ms to prevent the signal from going below 1ms when applying the brake. The result is a throttle signal that varies from 1ms to 2ms when fed a signal that varies from 1.5ms to 2ms.