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Old November 1st 06, 02:57 AM posted to rec.radio.amateur.antenna
Jimmie D Jimmie D is offline
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First recorded activity by RadioBanter: Jul 2006
Posts: 296
Default Identifying coax cable.


"Harold E. Johnson" wrote in message
news:A1N1h.261969$1i1.61365@attbi_s72...

If it has a solid center conductor, it is almost certainly 75 Ohm. The
only
exception I can think of is some weird version of RG58.

Tam


I do have a bunch of older RG-58 with solid center conductor, and
pretty much all the HP BNC patch cables I've seen the insides of have a
solid center. I believe the various semi-official versions (RG-58/U,
RG-58A/U, RG-58B/U and RG-58C/U) tell whether the center is supposed to
be solid or stranded, but that seems to have become *******ized. A
quick Google search for RG58A yields cables with both solid and
stranded centers. How about Belden 9913? Of course, the construction
of that line is "different" enough that it would be hard to mistake it
for something else, and I assume the poster would have mentioned the
strange construction. Also, you're likely to find a solid center in
higher impedance line like RG62/U, and you're likely to find stranded
center on 75 ohm line (like RG-11/U, and others). And of course for
some surplus custom line, all bets are off about both stranding and
impedance!

Cheers,
Tom


Well, I was going to avoid this, but when you chimed in Tom, couldn't help
myself. In turn, I have a large helping of a Times Wire and Cable RG-8
size 50 Ohm coax with a solid inner conductor. Don't remember their
nomenclature for it but it's a real bear getting "N" connectors onto it..

W4ZCB


Solid could be 92 ohms too.