I still have my old CB and it is under my truck seat. Have the squelch all the way up and can only hear trucker reports when I cam close to them... My antenna is a door jam mount on my two side doors that open from the inside on my truck. CB on one side and Ham Radio/Scanner on the other side...
You can see the antennas on the rear edge of the rear doors here

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Never hear any RV folks on CB anymore... Still gets good road hazard reports from truckers and they are still very dirty mouths guys....
If I was going to mount an antenna on a CLASS A/C I would get the mirror clamp-on mounts or maybe something to mount to the rear ladder... No drilling required... Get from AMAZON....

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At the camp grounds we use the portable handheld radios from WALMART or our cell phones...
Roy Ken
