Gaspar. I quit making air retracts. But I am making electric retracts. The concept should be the same. Each gear has its own electronics on the top of the retract. Each gear also has a gear door sequencer designed into it. When you apply power to the gear, even if the receiver is off, the gear door's open and the gear drop down. The stay that way until until power is reapplied, the receiver is turned on, and the retracts are cycled 1 time before the work in the sequence for flight, and stay that way until power is turned off. The gear doors are are programmed to work in the standard or a P-51 mode by a switch setting. The direction of the servo is also done by a switch setting, The end points are setup in a program mode, which is another setting using a push button. on the board. The gear also cycle down if the battery voltage goes to low.

Larry E
SouthEast Model Products