Coaxial TV cable getting hot / Need wiring diagram

Sounds like there's a problem with the park cable, must have some leakage from the AC power at the pedestal, and finding its way to ground through your cable.
Alternately, there may be a problem with your TV, putting voltage (12 volts maybe?) on the cable, which in turn is finding a ground outside of your rig, via the cable. I would suggest a bit of investigation with a voltmeter to determine the real problem. Could present a dangerous shock hazard.