You may have wired into the wrong location.
Here is a had drawing of our trailer wiring.
The coax from the outside connection goes to the entertainment center where it is looped(a jumper strap). Then the coax goes to the antenna power box (green LED) and then back to the entertainment center.
If you want one box to feed the same channel to both TVs you insert the converter box where the "LOOP" is. If you still can not see the setup screen reverse the leads.
If you want it to feed just one TV then disconnect the coax feed into the TV and put that coax into the in connector on the converter box and then the out from the converter goes to the TV.
If this does not help ask more questions and we will try and help. It should work.
Cheers,