This is what I have. Could be correct it is not supposed be pulled out however is like an RG6 cable with a Center wire. If you can expand the picture, inside is a pin that goes into the cable to make contact with the Center wire. I believe if it was not supposed to be removed, I could maybe remove the sheath and attach or somehow make from a new antennae cable.
I have seen masts for sale however not close enough to see any detail of the end that is to go into the top of the base (from under the fender). It appears the shaft should come out of the top.
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Yep. The problem is attaching the center wire. No idea, I think it was done before the thing went together. You "Might" be able to drill an access hole in the opposite side of the base, re-attach the coax, and solder the lead wire. The ground connection surely must have been crimped somehow Ma never intended those to last 40-50 years LOL
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