Hi all I am new to retracts and I would like to know if their is a reason I can't use EPA on my transmitter with the retract servo. I have polks tracker II transmitter and seeker II receiver and Hitec Retract servo. Spa works for every thing else throttle elevator ailerons.

Thank Rob

Retract servos are either "up" or "down" there is no in between. The servo travels through 180 degrees (as opposed to 60 degrees for normal servos). Retract servos are not proportional, so EPA will not adjust them. All adjustment has to be through the mechanical linkages.

gus

Some time ago I looked into using a low profile high torque regular servo instead of a retract servo. It always seems that the retracts are either all the way on one side and not enough on the other, or too much on both. Anyway, problem with lo profile regular servo was not enough travel, and by the time I had a wheel mounted that was large enough, it (the wheel) was too large to fit into the servo bay, and I wasn't about to start cutting out center rib sections!


Retract servos have different electronics than regular servos, so no proportional movement at all...


Andy

As mentioned, retract servos are designed for 180 degree operation and are not adjustable via transmitter settings. There are several reasons for this. The servo won't draw unnecessary current while full up or full down. The servo arm will also be in the strongest holding position at either full up or full down as it will be parallel to the push rods. The key to setting it up is using the correct length of servo arm. Manually push one of the rods to move the retract from full down lock to full up lock and carefully measure the linear distance that the rod traveled. This will be the length of the servo arm from hole to hole where the rods will attach.