Many who hook up a CB for the first
time find that they have a high SWR reading of 3 or more.
The SWR reading must be between 1 & 2 for ideal communications.
If your ground wire from the antenna sheath is not grounded physically close to where it exits the sheath, you can get a high SWR reading.
You will see in the photo below where my ground wire is screwed into the side of the ARB bumper.
Also as noted bellow, if any of your antenna base or bottom mounting bolt comes into contact with any metal from your rig, it will ground short out your antenna and also make for a high SWR reading.
The positive wire coming from the coax
sheath goes between the bottom bolt of the antenna and a plastic washer.
This prevents that lead from getting a "ground to frame" connection.
That lead must not touch any metal.
Also your antenna base such as the
spring mount, or regular mount must not touch any metal on your rig.
That is where the two plastic washers come into play.
It (my spring, base below the spring, and bottom bolt) must be totally isolated from ground contact to the vehicle.
The ground wire from the coax sheath
must be grounded to frame near the exit of the sheath.
Mine is about 2" away from the sheath, and that it OK.
Anymore than that and you are pushing it.
I get a 1.0 to 1.1 match with my setup on all 40 channels which is very good.
My CB Section
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