Re: longitudinal waves

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Jim Lux by way of Terry Fritz <twftesla-at-qwest-dot-net>" <jimlux-at-earthlink-dot-net>



Tesla list wrote:
> 
> Original poster: "David Thomson by way of Terry Fritz
<twftesla-at-qwest-dot-net>" <dave-at-volantis-dot-org>
> 
> Hi Dave,
> 
> > One Assumes such waves ought to exist (....) at all freqs, and other freqs
> and sources are easier to work with...
> 
> They do exist at all frequencies.  Every EM wave is associated with a
> longitudinal and a rotational wave.  I can't imagine how it could happen any
> other way.
> 
> > >       There is a whole class of nearground and underground antennas,
> >>        for specialized applications in electromagnetic and radio
> >>        work.
> 
> I know there are underground antennas.  As you mentioned, they are ELF
> related.  But I'm not aware of any antenna structures designed to work
> directly off the ground.
> 
> Today I did the calculation for the longitudinal experiment I proposed.  The
> long wires need only be about 4.25 inches apart to pick up the target I have
> set at 1390KHz.  I've surveyed my yard.  I should be able to lay two 100
> foot wires 8.5" apart on the ground and oriented in the direction of the
> broadcast antenna to receive the waves.  The weather is looking good so I
> may be able to do this within the next week or so.

would this not just be a travelling wave antenna (sort of like a
rhombic?).. Presumably, you're going to look at the difference in voltage
between the wires?

You might want to take a look at some work by George Hagn on the Open Wire
Line (OWL) method for ground parameter characterization.  He did a lot of
research on the electrical behavior of pairs of wires laying on or slightly
in or suspended above the ground.  You'll need to take into account all the
non-longitudinal effects if you're looking for the longitudinal signal.
> 
> Dave