Wow, I've received a bunch of _very_ ingenious answers, but as they were
mostly private, I won't post them.
Still, it suggests some added clarifications:
1. As I live in Arizona, there is a summer 'monsoon' season with serious
lightning potentials. Some colleagues here tend to leave their tower
retracted in the summer when DX is scarce and lightning is more common.
I've seen cloud to ground out here out of clouds that aren't even _raining_
yet. Lots of it, in fact. So, I'm planning on at least some periods of
time with the tower routinely retracted. Lightning strike potential, per
year, is at least as strong here as anywhere else I've lived. It may be
the dessert, but lightning doesn't seem to care.
2. At least some of the time (probably all of the time), I will leave the
tilt-over feature in place. One advantage of the dessert is that I don't
have to worry too much about a stainless steel gadget rusting to start
with. Ditto the cabling. W0IBM, as I recall, left theirs out permanently,
too, with way more rain and snow. I'm assuming 120 degree heat isn't an
issue I should worry about if it's just "sitting there." I doubt if
tilting it over on hot days will be common.
3. Because the tilt over will be at least sometimes there and because the
finish on the cement is fairly rough, I don't want to see the coax and
control cable scuffed. Someone suggested I might consider netting to
"catch" the coax on lowering. That is an option to consider.
4. It appears based on available experience that I need something closer
to a 30 inch diameter than a 14 inch one. Noted.
5. Suggestions have also been made that there may be enough standoff in
the standoffs as to allow me to attach it to each arm as I really want. I
have not put those arms in place yet, so I really don't know how it is
going to line up, exactly. I'll look for opportunities to tie the coax to
the arms. That really would be my preferred solution. Some have suggested
giving up on remote raising/lowering and guiding the coax with some sort of
control ropes (I presume, dacron ropes). That would be another way to deal
with the snagging problem.
Again, "keep all those cards and letters coming." The ingenuity of this
group is nothing short of fabulous.
Larry Wo0Z
On Sun, Dec 30, 2012 at 11:16 PM, Larry Loen <lwloen@gmail.com> wrote:
> As many of you may remember, I have this (still) extended adventure going
> to put up my tower (a US Tower HDX 572MD). The tower is actually standing
> up, but, given I can only work on it during weekends, the "finish" work is
> taking forever.
>
> One of the next steps, though, is to design something that sits at the
> "base" to receive the coax as it coils up.
>
> The design of the tower that I have (unlike the former one at W0IBM that I
> generally take as my model) has its "stand off" arms all in alignment. We
> discussed whether I should let the coax fall all the way "in line" or try
> to affix it to each arm.
>
> US Towers said that hams did both, but I really don't see an easy way to
> prevent the coax from "snagging" on the lower arms after lowering it. So,
> the "fall through" approach seems prefered.
>
> However, with the tilt over fixture in-place (or even if it is not), I
> seem to require some sort of "tub" to receive the coax when I lower the
> tower or partially lower it.
>
> The most obvious choice is a circular tub, mounted on metal or perhaps 4x4
> inch wooden legs (maybe even with plywood reinforcement under the tub's
> bottom.
>
> I see an ad here:
>
>
> http://tsc.tractorsupply.com/tractor/Plastic-Tubs?reqUrl=http%3A%2F%2Ftsc.tractorsupply.com%2Ftractor%2FPlastic-Tubs&storeId=10551&zoneMarketInfo=2-45&storeZip=85138&storeCity=city%2C+state&catalogId=10001&langId=-1
>
> . . .showing an open, 25 gallon tub with a 14 inch diameter suitable for
> watering horses. Is this the sort of thing I should be looking at? Do I
> need smething bigger? I expect to have two or three coaxes (9913F type)
> plus some control cable (at least six eighteen gauge and two fourteen
> gauge) going up the tower with the coax. I assume I tape the control lines
> to a coax and maybe the coaxes together.
>
> I also seem to want to put in some sort of gadget at the top so that I can
> provide some sort of "rounded 'L' material at the very top to provide some
> strain relief for the coax which otherwise would bear the weight of a 72
> foot drop at one point. That seems a problem, especially in the 120 degree
> Arizona sun.
>
> I'm not totally thrilled with this, but I don't see a good alternative
> design because I don't see how to avoid the snagging issue. I'd rather
> attach everything to each extended arm, but haven't figured out how to make
> it really work reliably when the tower is anywhere near fully collapsed.
>
>
> Larry Wo0Z
>
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