Thread: Standing waves
View Single Post
  #8   Report Post  
Old September 22nd 09, 08:21 AM posted to rec.radio.amateur.antenna
Szczepan Białek Szczepan Białek is offline
external usenet poster
 
First recorded activity by RadioBanter: May 2009
Posts: 197
Default Standing waves


"Cecil Moore" ...
Szczepan Białek wrote:

"Cecil Moore" wrote
Since the forward current and reflected current are equal
in magnitude and opposite in phase at the ends, they act
like transmission line currents and the magnetic fields
cancel at the ends. They are in phase at the feedpoint -
hence the maximum radiation at that point.


It apply to 1/2WL dipole. But what radiate in 0.05WL dipole? There the
"maximum radiation " is in the transmission line (1/4WL from the end). The
feed point is also in the transmissing line.
"R. Clark wrote : "[* What is this proportional and
proportionate mean? For a dipole of
0.05 WL to a dipole of 0.5WL, the far field change for that 10:1
variation is negligible. However, for a dipole of 0.5WL to a dipole
of 1.25WL, the far field change for that 2.5:1 (a smaller proportion)
variation is very noticeable.]"


See what Richard Harrison wrote:
"At the open circuited ends of a resonant antenna there is almost double
the forward voltage but zero total current due to cancellation of the
forward and reflected currents at the open circuit. At the open circuit
in the wire, all the energy in the wave is transferred to the electric
field."


What I wrote agrees with what Richard H. wrote and vice versa.


Rather no. Richard do not write about a feed point.
S*