 |
Lightning damage risk
20 June 2014 | by I am always nervous about lightning strikes.
The excellent Southgate News today told the (true) story of a local CBer who had his vertical and CB rig destroyed by lightning. See http://www.huntspost.co.uk/news/latest-news/
huntingdon_cb_radio_user_almost_electrocuted_after_lightning_
bolt_strikes_aerial_1_3648368http://www.huntspost.co.uk/news/latest-news/
huntingdon_cb_radio_user_almost_electrocuted_after_lightning_
bolt_strikes_aerial_1_3648368
I usually disconnect antennas when there is lightning about but I am still nervous. One of my friends (not a radio ham and with no big antennas in the air) who lived in a normal estate home had his home struck years ago and it took out lots of his household wiring. The chances of a direct hit are rare, but I am always bothered and never quite sure what the best advice is.
3 Responses to “Lightning damage risk”
 Ham Radio Deluxe |
 Ham Radio Prep |
 KB3IFH QSL Cards  Hip Ham Shirts  HamRadioAuctions Reliance Antennas Enigma Shop |  morseDX  Ni4L Antennas  R&L Electronics antennas.us Ears to Our World |
- Matt W1MST, Managing Editor
A little fear regarding your rig is a good thing, respect the electrons! If your grounding system is maintained and you’re diligent in unplugging the feedlines (mains as well) all should be well.
Watch it: tomorrow I’ll get a surge on the dipole…
I’ve been struck by lightning. It came in through the mains and out through my 2m antenna which was disconnected from the radio at the time. It jumped about a 5cm gap from a device attached to my 2m radio, which included a gold-plated dipswitch, to the end of the coax. As I recall, it blew up my (cheap Radio Shack) power supply–there was about 7cm of pc board trace vaporized between the transformer and the filter capactor, and left a gold-plated burned spot in the middle of my table.
There’s not a lot you can do if the lightning wants in except follow good grounding practices. In the United States, there will be a service ground at the point where the electrical service enters the building. It is my understanding that if you have a shack ground, you must tie the shack ground to the service ground or you can wind up with a several thousand volt potential between the shack ground and the electrical service ground which can destroy your gear and start fires if you’re unlucky.
In 1996 my G5RV suffered a nearby lightning strike in amongst saturated trees. It had been raining heavily for days beforehand and I was at work when it happened. My kids were at home and they phoned me to say that the light in the TV room had gone out. When I got home I noticed the G5RV had a droop in it. I went down the garden to the far end had saw that the wire stopped short of the tree support at the bottom of the garden. I ran into the shack which was a separate wooden hut and the smell of carbon was overwhelming. I had detached the co-ax feeder but the surge had jumped eight inches across the bench and blown a hole in the casing of the Vectronics VC300 ATU then had travelled down the patch lead into the SO239 socket on the rear of the FT101E and carried on down the mains lead straight to the house tripping several circuit breakers and knocking out two of the three landline phones in the house. But I had special Amateur Insurance via the RSGB and they paid out for a new FT990 which eighteen years later is still going strong.
I don’t think you can reduce the chances of a lightning strike but you MUST have special Ham Radio Insurance for your shack – no doubt that it is money well spent.