I will be replacing my antennas shortly and want some humble (?) opinions
on stacking options vs mast strength. The tower is a TriEx LM-354 with a 15
foot 0.18 wall steel mast about four feet inside the tower to the rotator.
I live in West Los Angeles which is a fairly low wind area unlike the
canyons of the LA basin to the east. A TH6 has been residing about 4 feet
below the top of the mast for 19+ years without any problems. Options:
1) TH7 close to the top of the mast (probably 1 to 2 feet below the top)
with a 3 foot thick walled aluminum mast extension which would hold the
boom support clamp only (the TH7 mounted to the steel) and an A3WS below
near the top of the tower.
2) Reverse 1) so no need for the mast extension for the TH7.
A 40m rotary dipole goes in between the two and parallel to the booms in
either option.
I know you're supposed to put the heavier antenna at the bottom of the
stack. My preference is option 1 to keep the 20m antenna as high as
possible while allowing for approx 10 feet of separation from the A3WS
pointed in the same direction (vs. 90degs to minimize interaction at closer
spacing.)
Thoughts and opinions appreciated. 73, Steve WB6RSE
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