gareth wrote:
Consider 100W at 3.6MHz propagating along some 50 ohm
coax, which terminates suddenly but with 1/4 inch of the central
conductor protruding.

A piece of coax is not an antenna.

Now there's no difficulty in feeding all that power into that
1/4 inch because it is so short compared to a wavelength
that there is a uniformity of voltage and current along it,
and it will be essentially the same as that existing in the last
gnat's cock of the coax.

Wrong and shows an utter lack of understanding how antennas work.

Attach a hi-impedance scope probe to the end of that
1/4 inch and all the power being delivered through the
coax will be detectable right at the tip of that 1/4 inch.

But not the current in that 1/4 inch piece, which is the important part.

Now, will that 1/4 inch antenna radiate all the power that
is being successfully fed to it at 3.6MHz, or will the
configuration behave merely as an open-circuit with all
the power being reflected back down the coax?

The amount of power the will be successfully fed to it at 3.6MHz will
be miniscule.

A number of contributors to this NG claim that the 1/4 inch
stub antenna will radiate the full 100W at 3.6MHz,

If and only if the impedance of the 1/4 inch stub is matched to 50 Ohms
without losses in the matching device and the resistance of the 1/4 inch
stub is much less than the resistive input impedance of the 1/4 inch
stub.

This is something you just can not seem to understand no matter how
many times it is repeated or shown to be true.

but
I fear that they are sadly mistaken and that their associated
infantile outbursts are because they are in denial either
about their error, or cannot face up to a challenge to
their seemingly-religious faith as to what is happening.

I fear you are incapable of understanding how any antenna works.




--
Jim Pennino

"Brian Reay" wrote in message
...

He doesn't want to understand, he wants to stir up a long thread he can
pepper with abuse

Untrue.

and
claim he 'won',

Untrue. Once again you project your own failings. Also untrue, because I
am always willing to accept that I may be wrong, unlike yourself who
regularly changes the subject in order to avoid being challenged; a
strategy for which you are notorious.

while others who disagreed with him didn't understand the
subject.

Untrue, although they might have misconstrued and shot off at
a tangent, as you are wont to do.

As strange as it sounds, this seems to give him some kind of 'buzz',
perhaps his self esteem is so low that he
is driven to such measures.

Untrue.

Perhaps he is just a nasty individual.

Physician, heal thyself.

Once again, Brian, you have jumped into a technical thread only to
originate abusive remarks but without making any technical contribution.

Why do you behave like that?