Lightning

[KA4HJH]

>But as for AC... the very large rate of change in the electric field due
>to the strike generates very wide band AC in any conductor. I guess the
>current generates a magnetic field too. Hence, the clicks, and spots you
>hear and see on TV screens during strikes.

We got called out to a customer's house once to pick up a fairly new 
TV that, well, just wasn't working right and the customer was 
impossible to reason with on the phone. We got there and the picture 
was screwy alright--obviously needed to be degaussed really bad. Of 
course they thought their brand new TV (a console they bought from 
us) was some sort of lemon, blah blah blah. Since nobody knew what 
was wrong they sent us out there in an empty van, no tools or 
anything. All we could do was load it up and bring it back to the 
shop (for 30 seconds of de-magnetizing). NATURALLY we bunged up the 
finish going through the door (put a nice big dent in the front), 
which led to far worse trouble.

We found out (just before going through the fateful door) that 
lightening struck just outside the house the afternoon before they 
noticed the picture was messed up. They didn't even bother to mention 
that on the phone...


-- 
Terry Bowman, KA4HJH
"The Mac Doctor"