How to Install the SO-239 Ball mount
Drill the center 5/8 inch hole first. Use the bolt to secure the aluminum plate to the auto without the other plate behind it. With the antenna installed get everything vertical in two directions.
Once everything is located and secured you can drill thru the Holes in the aluminum plate to locate the holes on the auto. Just Be sure that nothing moves while doing this. To be safe you can Stick a bolt thru the first hole you drill before drilling the rest.
To insure that the ball mount does not slip, it is important that the locking bolt on the ball halves is really tight. That’s what binds the metal together.
You start by taking the ball mount apart to install the wire into the top halve of the ball mount. Any wire size up to 1/4 diameter can be used but one end will have to be cut off clean.
The SO-239 is removed from the top cup and the cable screwed onto it. The cup is then screwed onto the SO-239.
Take the top half of the ball mount and feed the wire thru and screw the cup back on by turning the ball and not the cup. That way you don't get a twist in the wire.
Feed the wire thru the ball mount still attached to the car all the way to the radio. And then put the ball mount back together.
You cut your wire to length at the radio and install another end to the cable to plug up to the radio.
SO-239 ball mount on 3 inch plates Model # 807 $ 130.00
SO-239 ball mount on 4-1/2 inch plates
Model # 808 $ 135.00
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