Michael A. Terrell wrote:

I saw both types on car radio antennas, and some was clearly marked
RG-62. Both types meet the original RG62 specification, they just use
two different methods to minimize dielectric losses, like fused disk
hardline used in CATV and other applications that require low loss
cabling. Also, why would one of the Delco engineers who designed their
car radios lie about the coax they used? He was explaining the then
brand new AM/FM/8-track combo when I asked a number of questions about
the RF front end. As usual, you will continue to believe whatever you
want to.

I happened to find a piece of the automotive cable -- complete with
connector -- in my junk box, which I'm pretty sure was cut from a
replacement antenna probably purchased in the '70s. This particular
cable lacks the PE "string", but the ~#31 center conductor is crimped in
a sort of zig-zag shape to keep it in place in the hollow tube. The
aviation cable apparently has the center conductor bent into a
(presumably loose) helix for the same purpose. I've never seen RG-62
cable without the PE "string", but don't have any trouble believing that
someone might manufacture it without the "string". I also don't have
trouble believing that some auto manufacturers might use RG-62. Although
I saw a lot of auto installations in the '60s, when I moonlighted
repairing such things, I never saw RG-62. But I certainly didn't see
anywhere near every possibility, and I could have missed seeing a marking.

Roy Lewallen, W7EL