just got this from someone and i want to test it. 3 screws on each unit.
want to hook it up without frying it.
both are numbered 123, so that easy enough. but want to know whats going on
electrically, is this just a reversing switch, I'm very very novice.

is there any free schematics out there, or can someone give me some basic
level input. I'm very green.

Ihave a 9513 unit and I guessed at it for another antenna.