Hi The lightning hit is both a great big voltage and a wallop of current. The voltage is the thing many people get worried about. Almost all of the damage I've had has come from current induced into near by conductors and similar magnetic field issues.
That said, the voltage spike has likely jumped several hundred feet to get into the vicinity of your house. Hopping from this to that while trying to run through the house is trivial compared to the distance it's already traveled. There are indeed ways to take care of this stuff. Some systems are set up for a "how many strikes per hour" type of operation. They do indeed run properly in a high hit rate environment. You do *not* want to foot the cost for an installation like that. Having the (insured) house burn down is much cheaper .... Bob -----Original Message----- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of MailLists Sent: Thursday, April 12, 2012 11:22 AM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Thoughts on lightning protection measures.... You're right, but it's highly depending on the used construction materials... The building I live in, is quite like a Faraday cage - reinforced concrete. Even higher frequency radio signals have a tough time entering, mostly through the windows. What I wanted to underline is that, even if the house would be build like a Faraday cage, any conductor from the outside represents a potential dangerous ingress path. Of course, the generated fields would affect any sensitive equipment, but with the low impedance path of an antenna cable, even the less sensitive ones could suffer catastrophic failure. Not to neglect are all the other conductors entering from the outside - power lines, metallic pipes, etc. "Full protection" is quite difficult, almost impossible, to obtain, but an antenna cable is the preferred path. On 4/12/2012 6:02 PM, Attila Kinali wrote: > On Thu, 12 Apr 2012 17:39:57 +0300 > MailLists<li...@medesign.ro> wrote: > >> Regarding the TBs, even if they are the only ones directly connected to >> the antenna, the cable is already punching through the house Faraday >> cage, and chances are quite high that the lightning discharge won't stop >> at them. > > A house isnt a faraday cage. Not by far. Unless you live in a box made out > of solid 5mm steal plates. > > If a lightning hits your house directly and is going down the lightning > rod down into earth there is a good chance that the electric and magnetic > fields you have in the house will fry sensitive electronic equipment.... > > > Attila Kinali _______________________________________________ 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.