Antenna Technical questions

[SteveE]

This is a question for the technical gurus out there. What is the characteristic impedence of the coax in our AM/FM radio antennas, or more correctly the coax that hooks the antenna to the radio? I want
to install a New Beetle style antenna on my bug, the antenna I bought from Real Source came with a six inch long coax (not nearly
long enough to connect to the radio). So I need to fabricate an extension, but I want to get the impedence right. Alternately does
anyone know where I can procure an extension cable(s). I need to run from the center rear of the roof under the headliner in the channel above the drivers side door down the inside of the A pillar and out into the trunk area. Any help would be greatly appreciated. TIA Steve E.

[GonzoBug]

Steve,Radio Shack should have what you are looking for. I bought one to install a trunk mount antenna on an old Ford a few years back. I'm not sure about the imp.
I hope this helps ! Gonzo