Hi Scarecrow and welcome to the RVUSA Forum. Your rig may not have come with a jack. Most RV's don't. I had to buy a 12 ton bottle jack for my Class C and take a bunch of 2x10 blocks along with it. And a tarp so I don't have to lay in the dirt to get the jack under the axle. But that's another story.
As for the coax connector - look in the vicinity of the shore electric cable. Mine is on the wall in the rearmost storage compartment.
Good luck and post back when you find it. Others may need that info.