I hesitate to continue this discussion which has nothing to do with Ten-Tec
equipment, but I will add that my 89' US Tower crank-up has taken maybe a
dozen direct hits that I am aware of with no apparent damage. It has a
Diamond F-22A 2M fiberglass-covered antenna on the top at 105', a Force-12
MAG-340 40M 3L at 100', and a Force-12 C-31XR at 90'. The Force-12 antennas
have floating parasitic elements. The two yagis are fed through an old DX
Engineering remote switch at the top of the tower. I thought it grounded
the unused antennas and all of them when it's off, but I don't remembering
modififying it to be that way, so maybe the unused antennas, including an
80M half sloper and 160M inverted vee, are floating.
I do see and hear a lot of arcing from the parasitic elements to the
grounded boom during storms, so the charge is getting drained off that way.
I didn't have that arcing when I had a Mosley TW-33XL 3L WARC yagi on the
top, but that antenna has all grounded elements.
I have ICE coax arrestors at the bottom of the tower along with ICE
arrestors on the rotor cable and the remote switch cable. I use ICE
aluminum blocks to connect #4 wire to the tower bracing, several ground rods
at the base and in the cable trench between the tower and house. The tower
is also connected to the nearby pipe fence of the horse arena. The ground
rods are connected with #4 solid attached to the rods with Cadwell
exothermic welding to assure good connections. I also have Alpha Delta
arrestors in the shack.
We have lots of lightning storms here in the desert near Phoenix. I do
disconnect the coax and control cables in the shack if I can. And now, the
Ten-Tec connection: My Orion is still working despite the storms. So far so
good.
BTW, I'll be moving from this nice set-up very soon. Anyone wanna buy the
whole thing? (I am planning on taking the Orion!)
Jim N7US
----- Original Message -----
From: "GARY HUBER" <glhuber@msn.com>
To: "Discussion of Ten-Tec Equipment" <tentec@contesting.com>
Sent: Saturday, July 02, 2005 5:42 AM
Subject: Re: [TenTec] Grounds, etc.
My experience with commercial VHF, UHF, and 800 MHZ - 900 MHz repeater
antennas at some 35 locations around the US has been that "antennas with a
DC ground potential" seem to avoid static build up and survive, unless they
are at the top and take the brunt of the lightning strike. "Your mileage may
vary" and the results could be very different of course.
73,
Gary - AB9M - www.csm-gh.com<http://www.csm-gh.com/>
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