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Re: [TowerTalk] US Tower damaged by lightning

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Subject: Re: [TowerTalk] US Tower damaged by lightning
From: <>
Date: Wed, 28 Apr 2010 19:05:32 -0400
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Sorry to hear about your lightning strike, Jim.  My tower in Cary. IL was 
hit a number of times.  Oce I happened to be foolishly outside and I saw 
(and heard) it hit.   It also got into my electrical system a few times but 
I never had the type of electrical problems that you do and I never had an 
antenna damaged.

I don't know why lightning would damage your steel tower cables.  I never 
replaced my guy wires after a strike.  US Towers recommends changing cables 
frequently, regardless of lightning, but very few people do it.  Personally, 
if I didn't see any damage, I would not be concerned.  Maybe it's time to 
move back to AZ : )


John KK9A / W4AAA

Subject: [TowerTalk] US Tower damaged by lightning
From: "Jim McDonald"
Date: Wed, 28 Apr 2010 08:22:32 -0500

My US Tower HDX-589MDPL, which is motorized with the remote control option,
recently took a very large, direct lightning hit.  The antennas on it at the
time were (and still are) a Diamond 2M/450 vertical at the top, a 2L M2 40,
a Force-12 Delta 130 30M rotatable dipole, and a 4L (+26M directors) SteppIR
at the bottom.

There are ICE lightning arrestors on the coax cables at the bottom of the
tower and a large grounding panel with arrestors on every coax and control
line at the house entrance.  I also have lightning radials with ground rods
every 16' going out from the base of the tower and the tower/radial ground
connected to the entrance panel, the telephone, and the electric ground
rods.  With one exception, all ground rods with connected to #4 wire with
Cadwelds, and the #4 wires were connected to each face of the tower with ICE
ground clamps on the cross bracings.

The lightning apparently struck the tip of the 40M reflector, which is bent
into a curl, and that element had the Phillystran linear-loading wire
support break off.  The large box of relays for the tower remote control
exploded.  Inside, the Yaesu rotor control, the SteppIR controller, and my
K3 were damaged.  The condition of my Alpha 87A is unknown, though the power
supply turns on, but the RS-232 doesn't work. I don't have another radio to
test it.  The 2M and 450 radios are fine; I would have preferred them to be

I haven't climbed the tower yet, but measurements from the ground indicate
the remote switch, rotor, and SteppIR are damaged.

My question concerns the US Tower repairs.  US Tower says the cable and all
pulleys need to be replaced and the tower inspected - all necessary to
ensure structural integrity.  The cables look to me to be undamaged, and the
pulleys seemed to turn, as I didn't have any difficulty lowering the tower
with a US Tower emergency hand crank.  BTW, anyone with a motorized tower
should consider getting the emergency hand crank in case the tower has to be
lowered when the power if off.

Obviously the relay box has to be replaced.  US Tower's price to travel from
Kansas to the Chicago area and do the work is unreasonably high, in my
opinion, and they haven't given me a technical explanation on why the cables
and pulley need to be replaced to "ensure structural integrity."  They said
that the inspection could be performed by another AWS-certified welder, but
I don't know of any locals with cable or pulley replacement experience.

Any thoughts on the need to replace the pulleys and cables would be
appreciated.  Yes, I have homeowners' insurance, but they also are going to
ask why.

Oh yes, one more question.  After the strike, my unfinished basement walls
have several cracks that we never noticed before.  The house is five years
old and is about 50' from the tower at the closest point.  Has anyone
experienced that?  I haven't been able to find any literature on the

Probably related, the water well is about 100' from the tower, and the water
was cloudy for two weeks afterwards.  The well guys said that the aquifer
can get disturbed in a lightning strike, causing cloudy water.

I have pictures at .  (The crawdad
was magically transported to our drive; the nearest pond is several hundred
feet away.)

It's a safe assumption that my wife isn't enthused about ham antennas these

Thanks for any information!

Jim N7US 


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