Greetings Jim:
Regarding ur lighting question. I took a 4th lightning hit this
evening (Sun); all since June 29th. This time on the 160M inverted
"L". The feed line end was over 75 feet from the house and the
flashover cooked our AM/FM receiver/ intercom (2nd time for that) and
I'm still looking for more stuff. The lightning "found" earth ground
at the base of the vertical portion of the 175 ft wire but cooked the
matching network but didn't significantly travel into the coax since
the network presented a higher impedance than the 1.5 inch gap from
ant wire to ground rod and 1200 ft of radials.
This is the 2nd flashover damage we've had. I have concluded that no
matter what precautions you take, if you are in the path on the bolt,
look out. Yep, a re-engineering project is underway. We are in the
2nd highest lightning ground stike zone in the world; Florida's Gulf
coast. To boot we are 135' AMSL on a noticable rise with no pine
trees close to the house (pine trees are great lightning rods).
PolyPhaser has a comprehensive lightning protection techniques
publication. $22 I believe now. I have it. We have a Ufer ground
system in house. What am I doing wrong? Living in an excessively
high lightning area, where a 130 foot ground rod can't get to 25 ohms;
that's what.
Gud luck
73 Sparky in Citrus County, FL
(Pete K4LDR )
--
FAQ on WWW: http://www.contesting.com/towertalkfaq.html
Submissions: towertalk@contesting.com
Administrative requests: towertalk-REQUEST@contesting.com
Problems: owner-towertalk@contesting.com
Search: http://www.contesting.com/km9p/search.htm
|