RE: Marx Generator and coupled antennas

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

Original poster: "Malcolm Watts by way of Terry Fritz <teslalist-at-qwest-dot-net>" <m.j.watts-at-massey.ac.nz>

Hi Dan,

On 28 Apr 2003, at 17:01, Tesla list wrote:

 > Original poster: "Mccauley, Daniel H by way of Terry Fritz 
<teslalist-at-qwest-dot-net>" <daniel.h.mccauley-at-lmco-dot-com>
 >
 > Getting a bit offtopic . . . sorry . . .
 >
 >
 > Anyways, I'm still working on my marx generator, but wanted to see if anyone
 > had experience with actually coupling
 > an antenna to the output of the marx generator to create a nice focused EMP
 > pulse.  The most difficult part of it would
 > be to match the output impedance of the generator to a 50 ohm parabolic dish
 > etc...
 > We did once do some research work on emp pulse weapons where we actually
 > charged a 50 ohm cable up to about 40-100kVDC from the center and then
 > quickly discharged it.  This would effectively produce a powerful, very
 > short (<pico second) pulse
 > which already had an impedance of 50 ohms which could be easily coupled to
 > an antenna.  However, the marx generator
 > would be much more difficult i would imagine.
 >
 > Any thought?
 >
 > The Captain

I built a Marx bank a few years ago which on testing, generated
enought electrical mayhem to damage half a workshop full of equipment
at a rather modest discharge energy of about 14J. Inductors were used
as charging elements rather than resistors and the thing was arranged
such that it formed a crude helix of inductors and gaps opposite each
other at each stage. It's a bit difficult to describe the
construction in a few words. However, helical antennae are known for
their directional capability. Output voltage was approx 300kV and
there were about 20 stages as I recall. Each cap was a home-rolled
poly of about 8nF.

Malcolm