In message , Rob
writes
Szczepan Bialek wrote:
The "dipole" where one element is connected to "live" wire and the second
to a "ground" is the monopole.

It is your misunderstanding that:

1. amateurs always connect coax directly to a dipole. they don't.
those that are in the know will use a balun.

In the past, many amateurs did connect coax directly to a dipole. The
reason is that - on most occasions - it worked perfectly well, and they
'got away with it'. It was only when problems occurred (interference to
TV, radio, Hi-Fi etc) that much thought was given to the need for a
balun.

In modern times, there is a lot more opportunity for amateurs to
interfere with - and suffer interference from - all kinds of domestic
equipment, and the use of a balun (or twin feeder) has more-or-less
become an absolute necessity.

2. the braid of the coax is "ground". this is not true. there will
be voltage at the braid of the coax at the antenna end when a balun
is not used.

Szczepan is obviously making the fundamental mistake of thinking that,
because the coax screen is grounded at the transmitter end (or at least
connected to the chassis of the transmitter), it is therefore at zero RF
potential - and that it is still at RF potential at the far (antenna)
end, where it is connected directly to the 'other' leg of the dipole.
This is wrong.

He is then assuming that if the coax screen is at zero RF potential
where it is connected to the other leg of the dipole, then the other leg
of the dipole is also at zero RF potential (and doesn't radiate). This
is wrong.

He is therefore concluding that as both the coax screen and the other
leg of the dipole are at zero RF potential, the only part of the antenna
system that is 'RF live' is the leg of the dipole which is connected to
the inner conductor of the coax - which is what happens with a monopole.
As a result, he is then claiming that a dipole is really only a
monopole. This is wrong.

However, I'm still convinced that Szczepan knows far more about radio
than he appears to, and is cunningly trying to get us to explain
phenomena which maybe we really don't know as much about as we like to
think we do!
--
Ian