"Steve" wrote in message
...
Probably proportionately more will be lost as heat as a very short
antenna will be a low impedance, therefore current, driven job and I sq*R
losses within the antenna will play their part. Apart from those
additional losses, it should radiate all that is left,

Some will be radiated, but in a short antenna, much less than with a
long antenna. That which is not radiated will reflect, or bounce off the
end and arrive back at the feed point.

"gareth" wrote in message
...
"Steve" wrote in message
...
Probably proportionately more will be lost as heat as a very short
antenna will be a low impedance, therefore current, driven job and I sq*R
losses within the antenna will play their part. Apart from those
additional losses, it should radiate all that is left,

Some will be radiated, but in a short antenna, much less than with a
long antenna. That which is not radiated will reflect, or bounce off the
end and arrive back at the feed point.

If the short antenna is a dipole, then the two reflections will be
considerably out of
phase, resulting in vector cancellation, which will also contribute to
reduced
efficiency of radiation.

On 22/10/2014 19:09, gareth wrote:

Some will be radiated, but in a short antenna, much less than with a
long antenna. That which is not radiated will reflect, or bounce off the
end and arrive back at the feed point.

How might you modify that statement to deal with a situation where the
"short antenna" is a quarterwave GP, and the long antenna is a
three-quarterwave GP?

"Jeff" wrote in message
...
On 22/10/2014 19:09, gareth wrote:
"Steve" wrote in message
...
Probably proportionately more will be lost as heat as a very short
antenna will be a low impedance, therefore current, driven job and I
sq*R
losses within the antenna will play their part. Apart from those
additional losses, it should radiate all that is left,
Some will be radiated, but in a short antenna, much less than with a
long antenna. That which is not radiated will reflect, or bounce off the
end and arrive back at the feed point.


Incorrect, all the power that is not lost as heat will be radiated, power
is not reflected at the end and bounced off to arrive back at the feed
point. Look at the different current distribution on a short dipole
compared to a 1/2 wave dipole.

Where do you think that the standing wave pattern on a half wave comes from,
then, for you need a reflected wave to create such a pattern?