That is worth trying. Very interesting web site as well - lots of info about
knots.
Thanks!
73,
Jack, W6FB
> On Sep 27, 2025, at 10:29 AM, Rob Katz <rob.katz@worldlegacy.com> wrote:
>
> Jack,
>
> Here’s an alternative to severing your coax to install a Kellum grip. You
> can use some rope with a whipping knot to provide the same function as a grip
> (I use 3/16” black Dacron rope). I’ve used these knots for decades on 50-75’
> of BuryFlex and hardline hanging down to the ground, with no slipping at all.
> I’m careful to lay the wraps as tightly as possible, and then the weight of
> the coax provides the final tightening of the knot.
>
> https://www.netknots.com/rope_knots/common-whipping
>
> 73,
> Rob K4OV
>
> On Sept 26, 2025, at 5:21 PM, Jack Brindle <jackbrindle@me.com> wrote:
> Brian;
>
> Last spring I replaced the coax on my A3S-JK with a new (and longer) length
> of
> Bury-Flex. I did a great job of soldering on the PL-259s. It wasn’t until I
> had it connected to the choke and fully wx sealed that I realized I forgot to
> install the Kellum Grip. I have spent quite a while trying to figure out how
> to
> slide one over the PL-259 to no avail. I will shortly go out to the tower
> base,
> cut off the bottom PL-259, slide on the Kellum Grip, then re-install a new
> PL-259. But not in 95+ degree heat we are still having.
>
> I have found that the one antenna type that absolutely must have a choke is a
> vertical. Without it the coax will provide a return for the current (no
> matter
> how many radials) and give all sorts of problems. If I were to put one of
> those
> up (K9YC-style with tall trees holding up the antenna at over 100 feet), and
> forgot to add the choke, I guarantee that I would be out winding the coax
> (with
> installed PL-259) through the toroid to get the results I need. Jim’s method
> of
> installing verticals is to use a single piece of coax, remove the jacket and
> shield for 1/4-wave to form the top portion of a dipole, then add a choke
> 1/4-wave down from the “feed” point. No connectors needed until it gets down
> to
> the shack entry. Large toroids are very useful here. Having said that, I am
> pretty sure Jim placed connectors at the lower end of the dipole.
>
> But, I wonder, how important is it to have a choke at every current node?
> Having one at the antenna feed is important, and perhaps at the shack entry
> point. But does the modeling really show that we need them in-between?
>
> 73,
> Jack, W6FB
>
>
> > On Sep 26, 2025, at 4:08 PM, Brian Beezley <k6sti@att.net> wrote:
> >
> > "Why sever the connector? If we are talking about RG-213 size coax, that is
> > .405 inches in diameter."
> >
> >
> > Sever the coax. I assumed the desired spot was far from the shack and it
> > would be too much trouble to fetch the end of the coax and then wind the
> > whole length several times through a large core. But maybe not! And maybe
> > installing connectors isn't that much trouble for someone good at it (I'm
> > not). I'd just want to be sure I had the right spot first.
> >
> > A quick model of the two-wire current shunt didn't look that promising, at
> > least for the initial geometry I picked. I'm not sure the idea is worth
> > pursuing.
> >
> > Brian
> >
> > _______________________________________________
> >
>
> - -
> <WorldLegacy logo swooshes 25%.png>
> Rob Katz, Director
> rob.katz@WorldLegacy.com
>
>
>
>
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