aemeijers wrote:
Red Green wrote:
terry wrote in
:
On Oct 15, 11:45 am, "Dave" wrote:
Was talking with someone the other day and mentioned that I had just
grounded the TV antenna (the mast, actually) to protect against
lightning strikes, and they said that was not such a good idea
because lightning is more likely to strike a path that goes straight
to ground. Now I am no
t
sure what to do. Anyone have any input on this topic? Ideas are gra
tefully
received...

Thanks,

Dave
Nah. Don't bother the lightning; if it strikes the antenna will go to
ground through the TV set etc. (probably blowing the sh*t out of
it!). And then find a way to the home's water supply pipe through
Grandma's vintage silverware.

More seriously: Some may remember church towers that had heavy copper
strips from ground to a spike on top of the steeple etc.
The idea being to try and discharge the high voltage of an incipient
lightning strike before an arc occurred.
Metal boat masts should be 'grounded' to the water for similar reason.


Church behind my house in VT took such a hit a couple of years ago
when I was there.

Pics of big bang result and rebuilding on pg 72.
http://www.town.williston.vt.us/webs...rt/annrept.pdf


http://www.usatoday.com/weather/news...r_N.htm?csp=34

So what are you supposed to do if antenna is on opposite side of house
from electric service and ground stake, and no plausible way to run a
cable between them? Yes, this is an actual question.

--
aem sends...
Hi,
You can use a ground rod at the base of antenna tower. Good way of
testing quality of ground rod is try to light up a light bulb between
ground rod and hot wire from house power wiring. If the bulb lights up
bright it is good. As a ham operator my grond is 3 rods tied together in
triangular pattern. Also the holes have charcoal pieces in them.
Also it is OK to install ~2 Meg. Ohm resistor across coax leads or twin
leads to bypass static build up.

If you got struck by direct hit even good grounding is not a safe bet.
Once I had a direct hit on my super large scale IT system located in the
basement of 7 story building. It knocked off main power breaker situated
in the next room with back up M-G set, wiped out most of data from
mass storage sub-system randomly. 3 day and nights to restore the system
from back up. So my idea on lightning strike is there is no 100%
protection. In my 50 odd years of HAM operation I never suffered a
lightning damage to my equipment. I have been lucky.