1) The "booster" is not a booster. It is a powered switch for the cable management system. When "ON" the cable signal coming from the roof antenna is routed to all the TVs in the camper. When it is "OFF" it switches the cable signal from the outside "CABLE" connection to the TV distribution system.
2) It is a 12 volt power source for the amplifier located in the roof antenna. Power is only available to the roof antenna amplifier when the switch is "ON."
3) The switch ONLY routes the signal. IF the signal coming from the campground is scrambled and you need a box to watch it, you will need a box for each TV.
See the manual attached.
There IS a "work around" by doing a mod to the wall plate. NORMALLY this mod is used to route a satellite signal to a receiver and then to the distribution system, but could be used to route descrambled cable TV to all camper TVs.
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Lou & Freya the wonder dog
2008 GMC Sierra 3000HD Allison Duramax
2019 Flagstaff 8529FL
The purpose of the 'cable box' is to access digital signals. Some parks have experienced problems with the digital signal & have gone back to the old analog system which doesn't require a box.
I use a box when I'm driveway camping if I'm not using my satellite dish.