If there is a continuous path from one anchor to another, thru the guy wires
(i.e. no insulators) you have a battery and current will flow - how much
depends on the soil, wetness, ph etc.
A rule of thumb is 1 amp flowing for 1 year will remove 20 lbs of material.
Many of my towers do have insulators, but a few don't. I'm not overly
concerned about HF interaction, but I do plan to break them up to stop any
current flow. I am very interested in measuring the current flow after I do
that, to see what it may have been.
I became more aware of this when a large pipeline was built near to my
property. They maintain cathodic protection of course, and I wanted to make
sure their currents weren't using my anchors as sacrificial anodes. I was
told by their cathodic protection specialist that a large TV tower in
Manitoba was lost due to this action. . The guy was in cement but had about
6 inches of dirt /grass accumulated on top of the anchor, which concentrated
the current flow over a small area. It eventually failed.
Sleep well...
73 Don
VE6JY
----- Original Message -----
From: "Tom Frenaye" <frenaye@pcnet.com>
To: <towertalk@contesting.com>
Sent: Tuesday, April 29, 2003 05:24
Subject: [TowerTalk] anchor failure from corrosion?
>
> I hadn't ever heard of guy anchors on ham radio towers failing because of
corrosion I'm wondering if it's something all of us need to worry about -
anyone with firsthand experience?
>
> -- Tom
>
>
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