Hi Press,
Perhaps i was unkind in my remarks about "foam" and 9913, etc. My opinion
remains.
If you think my opinion is "suspect" then take note of the fact that i
condemned "flexible" cable with foam dielectric, not heliax with a much
better grade (read that "rugged")of foam. Hardly a blanket condemnation of
"foam."
As important as loss is, in the selection of a suitable feedline, it ought
to be balanced against ruggedness and durability, long life, integrity,
etc.
I am a believer in "soldering on " coax connectors, just the way the
manufacturers designed them to be installed. I dislike "foam" in flexible
cable because just thinking about getting the slodering gun is usually
enough to cause the foam to start evaporating. Consider:
Back about 10 years ago, Jim WD4MYM (now-SK!) approached me and asked me
to install some type N connectors on several hundred feet of 9913, for him.
The center conductor was of a different diameter than RG-213 and required
"special" center pins. The dielectric was foam and it started disappearing
the moment you put the heat to the connector or center pin.
The shield was tin foil with a few strands of wire on top of that. My
opinion ,formed right then and there, was that 9913 was CRAP! When the day
comes that i see something different about 9913 ,that endears me to it, i'll
be glad to change my mind. Till then, no way.(I'll look for you at Shelby
and get you to show me a small sample of modern day 9913 Press! :o) )
For my money, theres RG-8X, RG-213 and 1/2" heliax and open
wire/ladderline. I'm not a serious contester, don't lay awake at night
worrying about small fractions of a db,etc. but if i find the run is too
long for RG-213, i'll spend the money for 1/2" hardline. Celwave is the best
deal going these days, as far as i've heard, with 1/2" @ $1.85 for foot and
$24.00 connectors.
Another consideration with foam is peak voltage rateing. VSWR and
lightning can make the voltages across your cable go quite high. I'd chose
cable with a rateing much higher than the "clamping" voltage of your
transient supression. Etc.
73 Press, see you at Shelby! 73 Roy Lincoln WA4DOU
------------------------------------------------------------
On Sat, 28 Aug 1999 20:02:50 -0400, n8ug@juno.com wrote:
>
> There seems to be a lot of opinion, much of it unfounded, working its way
> into this thread.......
> 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.
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