The Kellem Grips look easier to use than my PVC sweep. I used a 2" gray,
electrical PVC which runs through the loop at the end of the coax arm. My
tower and arms are 1994 vintage, and I think the newer ones have smaller,
oval shaped loops; the PVC sweep wouldn't work on those, so the Kellem Grips
would make sense.
To attach the PVC sweep I used black 10 mil or maybe 20 mil tape that I
think is sold as covering gas pipe in the home improvement stores. I had to
be careful to position it so the bottom edge of the top of the PVC didn't
press into the cables. I taped the cables to the top of the standoff arm
with the same, heavy duty tape.
I've heard of others using a block of wood with a gentle curve taped to the
top of the arm too.
My 2" PVC filled up quickly with cables, so that the last cable with its
attached Yaesu rotor plug had to be taped to the outside of the tube.
Given all of that, honestly, if I were doing it over, I'd use the Kellem
grips if you could find the right size.
The US Tower ham catalog has their inverted vee (or whatever) hanger on page
3. http://www.ustower.com/uploads/pdf_file/HAM%20CATALOG.pdf . It's now
called an IV-16. The current IV-16 appears to use a U-bolt to faster to a
tower leg. That is a better design that my old one, which has a captive
mast sleeve and must be slipped down the mast before any antennas are
installed. The wire antenna keeps it from rotating when the mast is turned,
but I use a couple of bungee cords too.
The current production coax standoff arms in the US Tower catalog are also
different than my older ones. Mine bolt to the top of each section with
predrilled, matching holes. The current ones, on the same page of the
catalog, appear to attach to a leg with a U-bolt. In this case, I like the
ones I have because they have a two-point mount.
I don't think I'd encountered the suggestion to use a PVC sweep to ease
the strain on the cables. I used "Kellem grips," secured by small hose
clamps to the loop on the top standoff, to suspend the cables -- either
individually or in small bundles -- leaving some slack above.
I've never found Kellem grips in the "home improvement" stores, but my
local "real electrical supply houses" stock them.
On 03/24/11 11:23 pm, Jim McDonald wrote:
> On my US Tower HDX-589 I use factory coax standoff arms, with a 90-degree
> PVC sweep on the top one arm to minimize strain from the weight of the
> hanging cables.
> I use the US Tower inverted vee hanger just above the thrust bearing to
> support an inverted vee. It mounts as a sleeve around the mast and is in
> the UST catalog.
> I have used a short length of conduit attached to the top section with
> U-bolts to hold another inverted vee.
> I have a small aluminum bracket attached to the top of one leg of the top
> section to attach a half-sloper.
> I also have a DX Engineering remote switch attached to another leg at the
> top of the top section.
> It's essential, obviously, to be careful to keep the rotor loop of cables
> going to the mast from snagging in that stuff.
> I took pictures from the ground with a telephoto lens recently if you want
> me to send you any.
> Jim N7US
> -----Original Message-----
> I am finding it interesting to engineer a way way to attach things to a
> crank up tower. It looks like the cable standoffs are done with small U
> bolts. I'm considering having a light plate made to bolt to the outside of
> the face with pulleys.
> How do you attach things (like wire antennae or standoffs) to your
> Mickey N4MB
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