Not sure if this helps at all, but my antenna was ´´broken´´ in that the antenna never went down. Got perfect reception, the motor worked, but the antenna wouldn´t go down. I got a new Hirschmann power antenna on ebay for 42 dollars shipped to my door, came with instructions and free tech support. Install was very easy work, if not tedious, and the new unit runs smooth as silk.

I´d go with the OEM style Hirshmann unit. Very good item, and runs almost silent, unlike my stock unit.