"art" wrote in message
oups.com...
On 17 Jun, 16:13, "Mike Kaliski" wrote:
"John Smith I" wrote in
...

Actually, old news from 3 years ago ...

http://www.eetimes.com/showArticle.j...cleID=21600147

JS

The guy doesn't even seem to realise that height is one of the prime
factors
in optimising propogation, particularly at medium wave frequencies and
vhf.
Building a tall mast costs plenty of money and if commercial radio
stations
could broadcast efficiently from an antenna the size of a bean can, they
would have done it years ago.

This is surely just a couple of coils wound in opposite directions with
capacitive coupling and a capacity top hat to prevent coronal discharge
and
maximise current in the top half of the antenna. Basically a form of top
loaded, inductively wound whip antenna tapped somewhere up from the base
in
order to pick up a 50 ohm matching impedence at the design frequency. I
don't see any new or innovative principles at work here.

Now if he could make it work efficiently on all frequencies with 50 ohms
impedence and with no requirement for further matching or adjustment of
any
sort, I would be impressed. :-)

Mike G0ULI

Mike
The antenna is based on confirmed scientific findings of the masters
and can be proved mathematically as one would expect from such an
antenna.
It is true that what happens to radiation when it is formed is
important
but what is more important is to understand radiation in its formative
stage.
When this is understood then miniturisation comes to the fore that
may
well be more important than the TOA but then even this antenna can be
raised in height. There is a lesson to be learned here. The Yagi was
invented by the Japanese in the early 1920 where America embraced the
invention
and where Japan did not. That same invention proved to be one of
Japans
undoing as they never caught on to the importance possibly by
beurocracy.
This new antenna has been pushed aside by America where I am positive
other Countries are moving fast ahead and now have 3 years lead to
play with.
It is America this time that is complacent. The antenna is there,
the mathematics is there and Maxwells laws are still there, all of
which conform with each other both with this antenna and my Gaussian
antenna but who cares.
Art Unwin KB9MZ.......XG

Art

There is a place for miniaturised antennas, particularly for military
applications where size and weight of the antenna outweigh other
considerations which are important to commercial and amateur users e.g
bandwidth and efficiency.

The yagi has great front to back ratios and makes for a great if slightly
narrow band antenna for UHF TV reception here in the UK. These antennas are
generally sold tuned to cover the local TV frequency channels rather than
the whole of the UHF TV band. A lot of people will need to buy new antennas
when the switch over to digital TV broadcasting takes place as the digital
channels have been arranged to be at the opposite ends of the band to
analogue TV in most areas.

The yagi was probably the first antenna that did not conform to antenna
theory as it was understood at the time it was developed. Small loops and
E-H antennas also appear to defy logic at first glance but careful analysis
of their performance has revealed how they work with higher efficiencies
than previously believed possible.

Unfortunately for some, there is no magic or defiance of the accepted laws
of physics involved in the way they work.

There are still areas which provide fertile areas for experimentation,
particularly at the extremes of the radio frequency spectrum.

Regards

Mike