I have a Force-12 340 (3L 40) at 101' and a C-31XR below it on the same mast
at 90'. On top of the mast, at 105') is a Diamond F-22 2M
fiberglass-covered antenna.
When I lived in New Mexico, I had a Mosley TW-33XL (WARC version of a
TA-33), which has grounded parasitic elements, above the 40, and the
tribander then was a KLM KT-34XA. I had no arcing from the 40M parasitic
elements to the boom during storms, though I do now. N6BT told me that was
because the top antenna shielded/protected the 40M yagi, which has floating
parasitics. (The 89' tower was at only 49' due to local zoning.)
I have Scotch electrical tape between the boom and the centers of the
elements of the 40M antenna but I get lots of arcing/popping during storms.
The choices:
1. Ignore it - it's a good static drain.
2. Rent a boom truck and ground the centers of the parasitic elements on the
40M yagi.
I have seen four direct hits during a 30-minute period in one storm here in
Arizona, and probably others have occurred too. No apparent damage. Have
several 8' rods at the base and in a coax/control line trench to the shack,
ICE protectors on the coax cables, rotor line, and DX Engineering switch
cables, and the ground rods connected to a large horse arena pipe fence near
the tower. Use mostly Cadwelds to connect wire to rods.
Jim N7US
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