There seems to be a lot of opinion, much of it unfounded, working its way
into this thread - perhaps a few thoughts might help guide some of the
undecided.
First and foremost, it should be realized that coaxial cable design and
construction is based on satisfying specified needs. There is a place for
solid dielectric, semi-solid (aka "air") dielectric, and foam dielectric,
the three major types; just as there is a place for considerations of
aging, power handling capability, mechanical capabilities, loss,
environmentals, shielding, size, weight, etc.
Unfortunately, many coax decisions in the amateur radio community are
based on very different criteria - these include "if a little is good, a
lot must be better," cheapest, lowest loss, and "my Elmer said ..... so
that's good enough for me," as well as some measure of the right reasons.
One commenter cited, in effect, that all foam is junk, and hard line is
the only answer, or at the least, Times' LMR. Since practically all
hardline is foam, as well as all LMR, this opinion has to be suspect.
Foam technology is an evolving science, and there is a tremendous
difference in the old wartime resource stretching material and the wide
assortment of ever improving high tech material available today.
As a matter of fact, only the HF bands are not dominated today by
foam type coaxial cable, and the inroads there are impressive, if not
always justified. Most full power HF stations with runs under 100 feet to
the antenna simply don't need a better coax than RG213, and "barefoot"
stations could participate with little restriction with
a simple RG58. I realize the all of you big guns or wannabe's wouldn't
consider it, but y'all aren't the majority - it's still a big, broad
wonderful hobby with room for all!
Belden has indeed run into trouble with their 9913F, and it is most
surprising, given their level of technology. I'm reminded of the
introduction of the original 9913 to the amateur market at Dayton many
years ago. We stopped on the way at the Richmond, IN plant at midnight on
Thursday to pick up the first production - we had asked for 5000 feet - 5
reels. As it turned out, there was only 1-1000 footer, and the rest was
little reels of everything from 100 to 500 feet. It all sold on Friday,
and it was some of the worst stuff we ever carried. It only had 60+%
braid shield over the foil so you could hardly find a wire to solder to
when installing a PL259, and within a few weeks the reports of water
running out of it at the transceiver appeared. But hey! it had 40% less
loss than RG213 or most any other RG8 type, so the stampede began.
Happily, Belden increased the braid % to 88 and we learned how to keep
the water out, and later make a flexible version. It won the race for
years, until Times and others developed the new foams which have left the
solids and "airs" in the dust.
Belden will solve the foam problems with 9913F as well, for those who
want it, but that multitude only encompasses a small crowd who actually
need it. The latter have a choice right now of several coaxes, readily
available, state-of-the-art, models that are within a tenth or so db's of
the 9913F's loss characteristics, and are tougher and longer lived, rated
as good or better in that respect than even old workhorse RG213.
Our advice is to avoid the hype, study the specs, talk to the
professionals in the business who are ready, willing and able to help. It
will cost you less, improve your station performance, and cure your
headache.
73,
Press Jones, N8UG, The Wireman, Inc., Landrum, SC, 29356
Sales (800)727-WIRE(9473) or orders@thewireman.com
Tech help (864)895-4195 or n8ug@thewireman.com
http://www.thewireman.com and the WIRELINE news
and bargain page. Our 22nd year!
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