Hi In the same area of "what I have seen". I used to live in a neighborhood where strikes were quite common. It was a rare summer month that there was not one or more hits in the neighborhood. Nobody's house burned down. They (I) did not loose every electronic device within 100' or 1000' of the strike. The thing *least* likely to be bothered turned out to be stuff with receivers in them (radios and the like).
Bob On Apr 12, 2012, at 6:58 PM, EB4APL wrote: > Hi, > > I have a personal reference: In the Deep Space tracking facility where I > used to work some 20 years ago it was very common to have minicomputers > damaged by strikes in the antenna. This antenna was located about 1000' from > the control room and there were an elaborate grounding system both in the > antenna (mainly intended to protect from lightning) and in the control room, > but we got TTL chips damaged very often during thunderstorms. The common > believe was the high currents induced in the ground cabling caused voltage > spikes inside the computer cabinets enough to fry the chips. I don't > remember failures in the receivers, transmitters or other subsystems, but > minicomputers were the usual targets, one or two chips each time. > > Regards, > Ignacio, EB4APL > > > On 12/04/2012 23:21, Bob Camp wrote: >> Hi >> >> Do you have a reference for 100' distant strikes routinely destroying >> receivers? >> >> Bob >> >> -----Original Message----- >> From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On >> Behalf Of Chris Albertson >> Sent: Thursday, April 12, 2012 3:25 PM >> To: Discussion of precise time and frequency measurement >> Subject: Re: [time-nuts] Best location for a GPS antenna...? >> >> On Thu, Apr 12, 2012 at 11:56 AM, Randy D. Hunt >> <randy_hunt...@yahoo.com>wrote: >> >>> On 4/12/2012 1:10 AM, Heinzmann, Stefan (ALC NetworX GmbH) wrote: >>> >>>> What about mounting the antenna on the side of the metal pole, with the >>>> top of the pole extending a foot or more above the antenna? >>> >> Typically when a receiver or other radio is destroyed it was NOT because of >> a direct strike. A strike within maybe 100 feet is enough. There is a >> _huge_ EMP field around the strike. The field will induce large currents >> in any nearby conductors. Even if the strike is to bare Earth many feet >> from the antenna the potential of the earth is raised by say 1,000 volts so >> now anything connected between ground the power has 1KV across it. >> >> >> >> >> >> Chris Albertson >> Redondo Beach, California >> _______________________________________________ >> > > _______________________________________________ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
