Just to be sure you have done everything right - have to push the button on the Antenna WALL PLATE and select ANTENNA from your HDTV menu before the OTA ANtenna is selected to use... Then you have to point the OTA Antenna to a local Tower and scan in the digital HDTV signals into your TV memory. Now you can use your HDTV...

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When you had the RG Cable ldisconnected at the antenna that would have been a good time to use a multimeter and see if you read 12VDC coming from the trailer. That is what powers up the BAT WING booster amplifier which is turned on by pushng the button on the Antenna Wall Plate..
Cables can go bad as the RG cable gets moved everytime you raise the BATWING...
I would never do all of that not knowing for sure its bad... Could of unhooked it and hooked up a 25-foot RG CABLE and run out the window to check first...
Now you are committed to replacing something that may not needed to be replaced...
i.e. If you don't have 12VDC coming from the RG cable from the trailer side then the antenna won't work for you...
Roy Ken