Many hams have no lightning protection and even more have inadequate protection. ?If you live in an area where the lightning flash density is lower and the attractive profile of your site is less, the odds are in your favor. ?There are "only" about 250,000 homeowner lightning claims filed annually (2008), totaling $1.065 billion.
A map showing annual lightning flash density per square mile is at: ?http://www.vaisala.com/VaisalaImages/Product%20and%20services/NLDN%20CG%20Flash%20Density%20Miles%201997-2010.png
Having trees higher than the antennas offers no protection. ?Trees are attractive objects that increase the probability of a strike. ?A strike within >0.5 miles can damage radios, it doesn't have to be a direct strike. ?Even attic mounted antennas are not immune to damage, as one of our local hams found out last year.
I understand not everyone can justify a whole-house, well-designed lightning protection system. ?I just hate to see experienced hams recommending to others solutions like hanging feed lines 6' away or putting them in glass jars. ?
As far as "not trusting lightning arrestors", there are over 150,000 commercial radio towers in the USA that take lighting strikes every year that rely on Polyphaser, Alpha Delta, etc. suppressors to stay on the air. ? If properly installed, they provide a high probability of protecting equipment. ?The $5 "spark gaps" found at hamfests aren't worth a nickel, however. ?
There are often good deals on ebay for name brand suppressors that are new or pulls from decommissioned sites. ?I bought 20 new Alpha Delta Transi-Taps for less than $10 each including shipping for our local club's fan-dipole antenna party. ?And a group purchase of 650' of #6 copper wire at $0.40/ft. wholesale helped everyone afford proper protection for about $70, depending on how many ground rods they installed. ?We even have electric demo hammers available to help drive the ground rods.
Steve, W3AHL
---In ic7000@..., <anetherton@...> wrote:
I must first say that I don't have a tower, the trees are higher than my antennas, and we have not so far had a strike on this property since we moved here in 1957, and I have not been struck (stricken?) in my 35 years of Hamming. 57 years of crossed fingers.
However...
I have my electrics and radios grounded both to the water pipes, which the electricians and cable techs seem to want to connect, and to the earth itself outside my second floor window. I will likely throw in my MFJ-931 some day to try and halt RF in the shack, but I do not know how to protect from a direct hit, and my Elmer was a radio tech for a local communications specialist, and told horror stories about local commercial installations that were struck (stricken?), and totalled. Of course, most of these were on mountain tops, but it is not just mountain tops that get hit, and many times in the Summer I have heard the "SNAP! - BOOOOOM!!!!!!!) of a really close call here at the home QTH, but no direct hits.
I do unplug all equipment, especially now that it is all solid state and more computer than radio (I look at my modern rigs as computers that transmit RF), and are not as resilient to magnetic disturbances as the old tube rigs I seemed to get in my younger years. Also, living in a house with older wiring from the 1950's (2 wire plugs), I will even pull the power supply plugs if a storm is near, or when leaving the house in the summer.
I wish I had the money to do a complete lightning protection regime for my whole house, but I do not, and have to allocate money, such as, do I want a radio, or lightning protection? Plus, many of us rent, and though it might be safer, many landlords do NOT want all that lightning protection added. Plus, I do not trust "lightning arrestors" much further than I can throw a pig by the tail.
So, I ground everything I can, and remove the coax and antenna wires when it is even threatening a storm.
Hope I can make it another 35 years, but then I would be over 100...
73 to the OM's and 88 to the YL's!
KC4BO
Steve W3AHL