OK Jim when using the gear in the ordinary fashion two or three gears would be ganged in some fashion so that only one plug is inserted into your channel of choice in the Rx to control the up and down movement and all the power used down stream is provided through this port in the rx from the main Rx buss.

To separate from this power in the rx we use a Y cord that the plug from the gear or ganged gear two or three is plugged to the other side of that Y is where you plug the extra battery for the gear, Now the Red lead of the plug from that last Y chord is cut so all the current for the gear has to come from extra battery but your one plug that goes into the retract channel on your Rx still has a sense and ground lead so the switching function will still operate.

Very simple and increditably hard to explain without diagrams which are beyond me but here is how I figured it out just use a common Y cord and go ahead and cut the red lead next to the male plug now rig up your gear and battery and give it a go.

John