I believe the easiest boom to element mounting system is one I learned from
W9RE which is also shown (slightly different) in the ARRL antenna book with
the log-periodic antenna projects. This mount simply uses some aluminum angle
and one muffler clamp together with two hose clamps. For ten meter or fifteen
meter elements, 1.5 x 1.5 x 1/8 inch angle stock is plenty strong enough.
Drill two holes for the muffler clamp to fit your boom size. (Galvanized
clamps from Lightning bolt antennas are a great value). Slit each end of the
vertical side of the angle (horizontal slit parallel to long edge of the
angle) with a hacksaw. The slits are used to clamp the element to the
angle using stainless hose clamps (available at a great price from FarmTek).
If you want insulated elements, then simply sleeve the aluminum tubing with
the PVC pipe a la Force 12 before using the hose clamps to secure to the
angle.
This process is (1) cheaper than the 4 u-bolt and aluminum plate, (2)
quicker to fabricate, and (3) in my limited experience, easier to control
the quality of the finished product.
W9RE tells me he uses this system with larger (2 x 2.5 inch angle and two
muffler clamps) for his 20 meter antennas as well.
Terry Zivney, N4TZ/9
00tlzivney@bsuvc.bsu.edu
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