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Old April 6th 06, 09:56 PM posted to rec.radio.amateur.antenna,rec.radio.amateur.homebrew
Michael A. Terrell
 
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Default Question about auto antenna cable and connectors

Roy Lewallen wrote:

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


Some of the third party replacement antennas were made with military
surplus RG62, and had hand soldered motorola plugs instead of the OEM
crimped plugs. I cut up a lot of old antenna cables and stripped the
copper braid to use as solder wick by dipping it into liquid rosin. Some
had the plastic spacer for the center conductor, but most didn't. Some
weeks we replaced a half dozen car radio antennas, so I always had
plenty of copper braid at hand. years later I worked for a CATV company
repairing converters. The braid from the control cables was a little
under 1/8" when it was pulled tight and flattened by pulling it around
the blade of a screwdriver.


--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida