There are lots of approaches out there....one which is inexpensive, and
sure seems to work is one that:
K4XS has used, it is a very basic mount - he has used it for
years....judging by the number of rotor boxes in his shack I would say it
must work OK...the Italian ham magazine once ran a picture of Bills old
shack and the translation under the picture (loosely) was - "no, he does
not sell rotator control boxes".
The 'XS Sidemount:
Imagine the tower has three legs: A, B & C.
Bill uses one piece of right angle stock and u-bolts it to two legs of the
tower - this is mounted with the side of the stock parallel to the ground
being on the top, lets it is attached to legs A&B......
He then uses another piece which he mounts onto legs B&C slightly above the
other piece...this time the side of the stock parallel to the ground is on
the bottom.
These two pieces are at slightly different altitudes - they do not quite
touch each other....the actually extend past leg B and the two angles form
a V coming off the side of the tower...the point of the V is at outside of
leg B.
The V then has a triangular plate of aluminum mounted to both of the
angles...which are spaced apart (that altitude thing) by - you guessed it -
the thickness of that plate.
...so now...imagine two of these things.
They are mounted several feet apart.
The lower on acts as the shelf for the rotator. The upper one has a hole
through it with a PVC fitting in it to act as a bushing/bearing.
An upside down J made of galvanized water pipe passes through the upper
plate's bearing and into the rotor.
Voila.....
By making the upside down J have its horizontal component longer than the
distance from the center of the rotor to the far side of leg A or C, you
have the same effect as the commercial "Swinging Gates"....no, that is not
the new rock group from Microsoft.
This length allows for the boom, when mounted at right angles (when viewed
from above/below) to the horizontal part of the "J" to travel about the
tower for approximately 300 degrees of rotation before the tower gets in
the way again.
A dead spot in the SW quadrant for NA hams should be fine....you can still
catch your Pacific OK and not hamper SA path.
It works......though the picture is not zoomed in you can see what Bill has
been up to during his Summer break from teaching at the Florida Contest
Group website, or go directly to:
http://www.4w.com/deemer/k4xs.htm
(Yup.....Bill is back)
73,
Jim, K4OJ
Florida Contest Group - visit our website at:
http://www.4w.com/deemer/fcg.htm
The Florida Contest Group sponsors the Florida QSO Party, check out the FQP
website@:
http://home1.gte.net/wd4ahz/fcg/ssqp.htm
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