I would not use 9913 on a crankup tower. It's way too stiff and will bow
out. Over time, the constant bending will cause the center conductor to
migrate, affecting the cable impedance. I initially used the much more
flexible Times Microwave LMR-400UF, but even that was too stiff. I had a
near-disaster when the LMR bowed out, swung around the tower and got caught
on the motor housing (I have a remote-controlled tower and can't see it from
the control position.) Ever since, I've used RG-213 with no problems. That
should be fine on a 50-foot tower. However, some comparisons between RG-213
and Buryflex revealed that the latter is actually more flexible. It also has
much lower loss. You can get Buryflex from Radioware
(http://www.radio-ware.com/).
73, Dick WC1M
> -----Original Message-----
> From: Tower (K8RI) [mailto:tower@rogerhalstead.com]
> Sent: Monday, April 26, 2004 10:11 PM
> To: coulter@bellsouth.net; towertalk@contesting.com
> Subject: Re: [TowerTalk] Using Belden 9913 on a crankup?
>
>
> I used 9913 for years and then gave it all away after one
> lightening strike blew off the water proofing. I figured it
> just wasn't worth the risk.
>
> OTOH 9913 is not a good cable to use where flexing is
> encountered. The center conductor can migrate off center and
> it needs to make wide radius bends if long life is expected.
>
> I much prefer LMR 400 to 9913. It's slightly cheaper, or has
> been. It's one or two tenths of a db less loss and fits the
> same connectors. Both fit PL259s. LMR 400 is more rugged and
> can make relatively short radius bends. Much shorter bends
> with reliability than 9913. I believe (without taking the
> time to look it up) that LMR-400 extraflex has about the same
> loss as regular 9913, but is more expensive.
>
> I used 9913 for years without a problem, or at least I never
> noticed any. I liked it, but finding water running out of my
> rig after the lightening blew off all the water proofing was
> enough to cause a rapid switch to something better. I'd
> probably still be using it had that not happened.
>
> You'll also most likely find hams who have used the stuff in
> flexing situations with no problems (there are usually
> exceptions to most any set of
> circumstances)
>
> Good Luck,
>
> Roger Halstead (K8RI, EN73 & ARRL Life Member)
> N833R, World's Oldest Debonair (S# CD-2)
> www.rogerhalstead.com
>
>
> > Could somebody tell me if Belden 9913(not 9913 flex)is usable on a
> > crankup tower. What I am interested in, is if it is bendable enough
> > when the tower
> is
> > cranked down or will it bow out too much? Should I go to a more
> > flexable
> cable
> > for the run up the tower, or is it workable? This is for a 51 ft.
> > crankup. Thanks for your help.
> >
> > Todd
> > N4JRZ
> >
> >
> > _______________________________________________
> >
> > See: http://www.mscomputer.com for "Self Supporting Towers",
> > "Wireless
> Weather Stations", and lot's more. Call Toll Free,
> 1-800-333-9041 with any questions and ask for Sherman, W2FLA.
> >
> > _______________________________________________
> > TowerTalk mailing list
> > TowerTalk@contesting.com
> > http://lists.contesting.com/mailman/listinfo/towertalk
> >
>
>
>
>
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
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