On my RV even though it is not a Forest River product alot of them share slot of similarities, on my connections inside my RV on my livingroom tv I have 3 hook ups.
#1 is for air/cable, #2 is for outside tv and #3 is for Satillite. If I want to watch my outside tv on air I install a splitter their and short cables to connect the #1 to #2 and to my living room TV. Yours may be similar. If not for a test if you are on air, hook up a cable from your outside cable to your outside tv and do a channel scan. Good luck.
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