RadioBanter - View Single Post - EH-antenna: sensation or fraude?

October 17th 04, 12:10 AM

On 16 Oct 2004 13:07:25 GMT, (Fractenna) wrote:

I am still dreaming about an ideal antenna having not more than 10% of
wavelength and 100% efficiency. Thanks for all the posts, anyhow.

Bozidar, 9a2

Moderate/high efficiency with a 10% physical height is pretty easy to attain.
That's not an e/h antenna, as far as I am aware.

The e/h antenna appears to ignore the main point about Maxwell's equations:
changing fields generate changing fields. E' make B's and so on. You can't
separate a changing E field from its B field, and so on. Thus the premise is
wrong.

In a --very-- small volume (fraction of a radiansphere), any single current max
radiator is very inefficient. Similarly, any multiple current max radiator does
not exhibit constructive interference in the far field. That's the physics.
Antennas as a pure science are now an exhausted field.

73,
Chip N1IR

As I understand the theory behind Hart's 'EH' antenna, he believes that if the E
and H fields in the radiator are somehow caused to be out of phase the radiation
will be greater. We all know that when an RF voltage is applied to a conductor,
such as a single-wire antenna (the radiator), a corresponding current flows in
the radiator. We also know that the current flow produces both electric and
magnetic fields, and the crucial point in this is that the E and H fields are
inherently IN PHASE in time, but in space quadrature (90° apart). Physical laws
of nature as determined by Faraday and Ampere, and finalized by JC Maxwell, show
that the E and H fields are immutably etched in time phase, and nothing in the
feed configuration can alter that relationship.

Now along comes Hart, who says he can alter that relationship by inserting an
inductance in series with the radiator, which he says delays the current 90°
behind the voltage, and thus the H field is delayed 90° behind the E field.

I haven't read the claims in his patent, only the fiction appearing on his web
page, but if the claims reflect his misguided, and invalid theory about altering
the relationship between the E and H fields propagating along a radiating
element, the US Patent Office has established a new theory of electromagnetics
that contradicts Faraday, Ampere, and JC Maxwell.

What are we to do? Somehow we must fire the SOB's at the PTO.

Walt, W2DU

PS--don't you find it ironic that when radiation measurements are taken in the
far field the measured power already relates directly to the power delivered to
the radiator? Then if Hart's version radiates more power than the standard
radiator, where does his extra power come from. Looks like he's invented a new
version of the perpetual motion machine. After all, it's patented, isn't it? So
it's gotta' work.