On Tue, 25 May 2004 11:24:23 -0400 (EDT),
wrote:

Boltek makes a very nice lightning detector system
http://www.boltek.com/stracker.htm displaying both bearing and distance
of lightning strikes. I understand how you can do this with a couple of
nice crossed loops but the antenna for this system is a little plastic
black box 3" high by 2" by 1-1/2" connected to the main unit with Cat
5. Does anyone know, or care to guess, what's in the box?

Hi OM,

A simple design would be to connect each loop into the vertical and
horizontal channels of an O'Scope (one loop replacing the Time Base).

When you do this with signal sources, you get Lissajou patterns. Same
thing, more or less, when you get a lightning strike. The lobe of
excitation (an elongated loop) will point in the relative direction of
the strike (once you calibrate it, and consider you could be off by
180°). The larger the loop, the closer the strike, so there is an
inverse relationship to consider too.

This was a subject of a Popular Science article in the 60s.

73's
Richard Clark, KB7QHC