> I wouldn't recommend using cable ties, though. The little square
locking
>mechanism sticks out too much for my liking and it could hang up on the
coax
>standoff. I prefer to use just tape - then there isn't anything to hang up
and
>is slips right through.
Actually, I just use cable ties to fix the coax to the top standoff, so the
ties don't travel through the standoff rings. I tape the coax along the boom
from the balun to the top standoff, which is fixed just a few inches under
and to the side of the boom. Where the coax snakes through the top standoff
ring, I have it attached to both sides of the ring with small black cable
ties and Scotch 88 (to try to take the strain off the part of the coax held
by the ties.) This is where a Kellems grip would be much better. From there
the coax drops through the remaining standoff rings. Note that the tower
rotates from the bottom, so there is no need for a large rotor loop at the
top.
> Bob, N6TV, uses a big 'net fish lander' and his cables coil into it
on
>the way down and uncoils from it on the way up - very slick and practically
>foolproof. The fishing device has a big aluminum round frame with a sock of
>fish net and a handle that you hold onto to land a fish (sorry - I'm not a
>fisherperson).
That's a neat idea. It must be a really big net. I've thought about doing
something like that, but to work properly it would have to be mounted on the
tower itself, which would interfere with full rotation (it would hit the
base vertical member.) Higher up, it would be too close to the motor housing
(too great a chance of coax snaking out of the net and wandering over to the
motor housing.) Above that, it would be very difficult to reach in the event
of a problem.
A friend suggested a method used to dress cables on sailboats: 1) run the
coax through a large plastic pulley so that the pulley is located about
halfway up the bottom fixed section; 2) afix one end of a bungee cord to the
pulley and the other end to a tree about 30-40 feet away, with the
attachment point well above the level of the pulley (I just happen to have a
tree in the correct positon.) The idea is that when the tower is lowered the
bungee cord pulls the pulley towards the tree, which in turn pulls the
excess coax up and away from the tower. When the tower is fully extended,
the pulley and coax are pulled back to the tower, the bungee cord stretching
to acommodate. Presumably, there would be enough stretch in the cord to
allow my tower to rotate (not much give would be needed for that.) The trick
is to find bungee cord with the correct amount of stretch and tension.
Someone else suggested that it would be much better to run a rope through a
pulley on the tree and use some weights. I agree. I haven't tried this
design because I suspect that the weak link is the large plastic pulley. I
have a feeling that the coax will not travel smoothly through it. The design
needs some way for the coax to move smoothly through the point where the
rope is attached. Any ideas?
73, Dick, WC1M
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