sensar antenna question

[chasingsummer]

older motorhome, has what i think is amplifier on inside roof, 2 wire connections, that has a small piece attached to the wires, coax attached to other end of this small piece. small switch that turns on red led.
On roof is an antenna head which is new, it is mounted to 2 square poles that raise and rotates with knob on inside. recent trip had no signal. run coax from tv to pole and attach old set of rabbit ears and i have signal.
i know coax on roof needs replacement, but maybe connector on roof that feeds back to this plate that i think is am amplifier may also need replacement. can i get parts without replacing everything since roof mounts do not leak?
how would i know if new antenna head on roof which is this brand is compatable with the older stuff inside? how would i know if i have maybe an unamplified head on a amplified system, and would that matter? Is there a way for me to test these pieces.
any and all info is appreciated, i would prefer not to just ship you stuff just for you to identify and ship back. plan is for me to repair/ update what must be done. thanks bgk