Hey Paul...
I'll admit I'm no expert, but I think this "loop" is where the antenna & cable TV coaxial cables are joined. One input being just the antenna... the other from the outside cable feed. This "loop" marries the 2... and the amplifier switch module is located 'upstream' from there. When the amplifier switch is turned on, it overrides the cable signal.
At least, I think that's how it works. Otherwise, what's the purpose of that small loop of coaxial cable?
So if you can isolate which inputs on that loop are the cable and antenna feeds... you should be able to go from there.
BTW... when's that new truck arriving? Gotta be soon now, right?
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