Hi
     One of my hobbies is HO electric slot cars. These are run by small
electric DC motors. When they are set on the track backwards, the power is
reversed to the motor and they try to run in reverse. However, I bought a
couple of cars designed for drifting. When these spin in a turn, the power
going to the motor is somehow kept in the same polarization. Thus, the car
goes in to the turn, spins 180 degrees and drives back the way it came from.
This is the coolest thing. Now, I am wondering. How can I build a tiny
circuit to do this and install it in some of my other cars? What types of
components in which configuration will keep the power constant to the motor?
I am sure this was probably covered somewhere in my ham theory back in 1989.
Smile. 
     Thank you for your insights.
 
God bless,
Mark
 
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