@kj356 posted:...
I am thinking that perhaps what I need to do is to cut one of the wires to the throttle on the power pack and have this wired into a relay.
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Agreed. I think your idea is indeed the closest exit.
This is not an MRC power pack, but I'm inclined to think they are similar in concept. So you flip the Momentum switch to "ON". Then you have a slide/linear or rotary control that is really just a 3-wire potentiometer (variable resistor) when you look inside the box.
So to your point, you could have a relay that selects either the running speed voltage or 0 voltage...and the power pack's "momentum" circuit will smoothly accelerate/decelerate your engine. Of course this means you need to open up the power pack and splice a wire or two but I believe this is a better solution than messing with huge capacitors and the "baggage" they bring.
