Just came across this post elsewhere and though it worthy of sharing ...
comments or clarifications as it may apply to Ham installations? 73,
DavidC AA1FA
At our site, which is a TV station with a 500 foot
tower, a lightning strike on the tower seldom has done any
transmitter damage. What has happened is that long serial
computer lines in the building usually toast the computers
they are connected to. The man across the street has lost
just about every type of appliance since the tower was
installed in 1963.
The problem is not the lightning, but the EMF/Magnetic
field which is produced when the tower is struck. To prove
this, we make a dipole about 400 feel long with a 100 ohm, 2
watt resistor at the feed point. After the storm the dipole
was lowered, and the resistor was gone.
Lightning is tricky, and preventing damage is a guess at best.
Fred --> NOTE: To reply to me in E-mail, change the
Mailer Daemon to W8HDU. The Mailer is a "spam trap".
Visit the WLIO Television Web Site: www.wlio.com
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