As a side issue - one of the stations down in tampa ended up off the air for a week. A lightning strike melted their heliax and antenna system was destroyed. The antenna was on the top of a bank building (about 70 stories up.)-- using the building frame as ground, and then in the ground under the bank building.
The transmitter, luckily, was not destroyed. (significant damage of course) However depending on where you are, and the strength of the strike... all bets are off. One station I helped put on the air (which had -2- layers of copper plates in the trench between the transmitter shack and the studio with the trench under ground had the entire rectifier stack in a Collins FM transmitter melted, assorted other stuff there... the lightning then hopped into the trench (on the ground) - and destroyed all the monitoring gear in the rack where it terminated. .Of course, that is Florida, where lightning tends to be 2-5 times stronger than other spots in the country. KK4QDZ - Now with Extra Class Priv's, and a tiny KX3 to enjoy them! ________________________________ From: Don Wilhelm <w3...@embarqmail.com> To: elecraft@mailman.qth.net Sent: Tuesday, July 15, 2014 9:49 AM Subject: Re: [Elecraft] Unhook *ALL* connections before Lightning storm The alternative to disconnecting everything is to design your ham station to tolerate lightning events. There was a very good 3 part series in QST for June, July and August of 2002 that dealt with the design of a station for lightning protection. Those articles are available at http://www.arrl.org/lightning-protection. I highly recommend it. Some of the "ground rules" given in the article: All towers and masts grounded with buried radial wires and ground rods to spread the impact of a strike over a large area of the earth. Perimeter ground wires around any building with a driven ground rod at each place the wire changes direction. (lightning likes to travel in a straight line). Bring all services into the ham shack through a common grounded copper panel fitted with suppression devices - that includes feedlines, power, CAT5 cables, phone cables, and everything else. Keep any equipment or devices that are not powered/connected through the above panel out of reach of the operating position. There is no guarantee that the above steps will eliminate failures due to lightning, but it will go a long way toward achieving that goal. The real goal is to keep *everything* in the shack at the same potential during a lightning event. I have attempted to use those guidelines in the construction of my shack and antenna field. All my feedlines are automatically grounded when the station is turned off, and I do not attempt to operate when there is lightning nearby - and I get stay out of the shack during storms. We had a lightning event here last year that took out the Ethernet router, several switches, 3 computers and 2 network attached printers. None of the ham gear was damaged. 73, Don W3FPR On 7/15/2014 7:12 AM, Brian Alsop wrote: > This sounds like good advice. However, every connector socket on my > K3 is populated, ditto the computer, ditto the KPA500, ditto the KAT500. > > Pulling all wires when there is a potential storm threat is totally > impractical. Even if I did, I'm sure some of the connectors would > simply not last. > > I suspect others have similar situations. > > 73 de Brian/K3KO > > n 7/15/2014 10:58, Bill Blomgren (kk4qdz) via Elecraft wrote: >> And another warning: Nearby (like next door) lightning will be >> picked up by ANY long wires which end up acting as antennas. >> ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to billblomg...@yahoo.com ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
