RE: Tiller and boom support (de N4KG)
I use two short (10 -12 ft) nylon ropes with a loop tied in the middle.
The first loop is tied through the eye of a large pulley riding on the
"trolley" or "tram" line. The ends are then attached to the boom a
few feet each side of the center of balance using a PROPERLY TIED
Clove Hitch with the line and knot crossover on the rear side (away
from the boom). When lifting, this will cause the elements to tip
toward ground on the tower facing side. This support rope looks
like an upside-down Y.
The second Y - shaped rope is attached in a similar fashion with
the rope and crossover on the BOTTOM of the boom. The pull-up
rope is tied to the center loop of the Y and continues to a pulley
mounted on the mast (a few feet above the attachment point). This
attachment of the pullup rope lifts the elements slightly as the
antenna is raised by pulling on the pullup rope, AND because of
the Y connection, acts as a TILLER, keeping the elements parallel
to the pullup and trolley ropes.
The amount of tip and/or lift can be controlled by rotating the
clove hitches on the boom. It can be a bit tricky until you develop a
feel for placement vs. lift. (It is IMPERITIVE that the CLOVE HITCHES
be tied correctly. An improperly tied knot can unravel, dropping the
antenna!)
A short tiller arm (18 to 24" of aluminum angle) can be attached to
the boom at the balance point. Position it parallel to the elements
and pointing TOWARDS the tower. This eliminates the need for
the second Y rope and eliminates the need to adjust the position
of the ropes for tilt / lift.
When the antenna reaches the top, the elements will be pointing up.
Loosening (but NOT removing) the nuts on the U-bolt attached to the
tiller will allow the boom to be rotated back to horizontal.
I ALWAYS attach my trolley and pullup ropes to the MAST. It helps to
have a few feet of extra mast above the antenna attachment point.
This assumes a thick wall mast. NEVER use a GIN pole to pull
antennas up at an angle. GIN poles are designed for VERTICAL
LIFTS ONLY. Pulling to the side can BEND your $500 GIN POLE!
de Tom N4KG
On Tue, 02 Sep 1997 08:55:45 -0500 Lee Buller <k0wa@southwind.net>
writes:
>This weekend, K0TQ and AB0S spent a whole lot of time (6 hours) on
>K0WA's
>tower replacing the top section, mast, rotor, etc. They put up
>heavier
>stuff in preparation for a larger antenna. I want to thank them
>publicly.
>
>Although the larger antenna was not ready to ascent to new heights we
>did
>put up a TA-33 until the other antenna (TH-6DXX) is rebuild and ready.
>
>To raise and lower the antenna, we used the tram system described on
>the
>reflector earlier this year. My observations are as follows....
>
>===>Do not use nylon rope. It streaches way to much. Should be a
>help rope
>like a climing robe that will not streach.
>
>===>The sling has to be made just right or problems will occure.
>
>===>A "tiller" needs to be installed to keep the antenna parallel to
>the
>tram line....but...what is the best way to do that?
>
>===>The tram line rope needs to be tied at least 2 to e times higher
>than
>the sling height above the boom.
>
>Here are some of my questions.....
>
>Do you use a come-along to tension the tram line?
>
>Do you use 1/8" aircraft cable for the tram line so there is no flex?
>
>How do people make the sling on the boom? We used norman hemp, tied
>in the
>middle and balanced. Do people you cable that is semi-perminantly
>installed?
>
>How long is the tiller and does it lead or follow the boom? Does it
>have
>its own pully...or do you use a carabiner? How tight is the tiller
>attached
>to the tram rope/wire...in other words...do you use a rope to attach
>the
>tiller to the tram line or do you use something rigid?
>
>Comments from the experts are needed. The TH6 is waiting and the
>bands are
>getting pretty good.
>
>
>Thanks people....
>
>Lee Buller
>k0wa@southwind.net
>
>
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