Add this servo amp H-bridge and a 5K potentiometer to any small motor, and you can turn it into an R/C style servo!

Control = R/C control 1.1mS - 1.5ms - 1.9ms
Channels = 1 (single motor controller)
Voltage = 4.8vdc - 6.0vdc
Continuous Current = ~2amps/6.0vdc (estimated)
Peak Current = 4.8amps/6.0vdc