Revisiting the Power Explanation
 

Allright, Richard, then where is the load when there are two vertical
radiators spaced 1/4 wl and fed in
quadrature, such that their individual fields are omni-directional in
azimuth, but when the two fields
combine, a maximum greater than either of the individual fields is
propagated in one direction, while a null
results in the opposite direction, negating the propagation of the
individual fields in the direction of the
null. What is your explanation of the negation of the propagation of the
individual fields when both radiators
are radiating equal EM energy? Are you still denying that interference is
not the cause of the modification of
the resultant fields? So I repeat the question--where is the load in this
case?

Walt

Shoot Walt, even I can answer that one. The load is called a pair of
vertical radiators spaced 1/4 Lambda and fed in quadrature.

W4ZCB

Revisiting the Power Explanation
 

"Harold E. Johnson" wrote in message
news:HBUPh.24578$_c5.3773@attbi_s22...
Allright, Richard, then where is the load when there are two vertical
radiators spaced 1/4 wl and fed in
quadrature, such that their individual fields are omni-directional in
azimuth, but when the two fields
combine, a maximum greater than either of the individual fields is
propagated in one direction, while a null
results in the opposite direction, negating the propagation of the
individual fields in the direction of the
null. What is your explanation of the negation of the propagation of the
individual fields when both radiators
are radiating equal EM energy? Are you still denying that interference is
not the cause of the modification of
the resultant fields? So I repeat the question--where is the load in this
case?

Walt

Shoot Walt, even I can answer that one. The load is called a pair of
vertical radiators spaced 1/4 Lambda and fed in quadrature.

W4ZCB



Harold -- I'm going to do a 'Cecil' on you...;) Wrong! The load is the
space into which the antennae is radiating!

The devil made me do that! Sorry.

Dean -- W4IHK

Revisiting the Power Explanation
 

Harold -- I'm going to do a 'Cecil' on you...;) Wrong! The load is the
space into which the antennae is radiating!

The devil made me do that! Sorry.

Dean -- W4IHK

Hi Dean, these guys have WAY too much time on their hands. If they had a
life, I'm sure they wouldn't know what to do with it.

Regards
W4ZCB

Revisiting the Power Explanation
 

On Apr 1, 11:55 pm, "Harold E. Johnson" wrote:
Harold -- I'm going to do a 'Cecil' on you...;) Wrong! The load is the
space into which the antennae is radiating!

The devil made me do that! Sorry.

Dean -- W4IHK

Hi Dean, these guys have WAY too much time on their hands. If they had a
life, I'm sure they wouldn't know what to do with it.

Regards
W4ZCB



- Hide quoted text -

- Show quoted text -

Hi Harold,

I've found out that it takes a lot of time to spar with Richard C.
When he gets ya he won't let go. He and I have somewhat different
backgrounds--he's an English major, while mine are math and physics.
That's probably why his definition of 'interference' disagrees with
mine.

As you've probable already determined, I maintain that modification of
an antenna pattern from that of a single dipole results from
interference between the fields radiated from more than one radiator,
and the pattern is determined by the relative phase between the
interfering fields. Kraus developed 'interferometers' to analyze the
field relationship between the fields radiated from the radiators in
his radio telescope. What more does one need to understand the effect
of interference? SWR on a transmission line is another example of
interference, that between the forward and reflected, is it not?
Thanks for permitting me the 'time'.

Walt, W2DU

Revisiting the Power Explanation
 

On Mar 29, 7:33 pm, Cecil Moore wrote:
Unless it is located at a
physical impedance discontinuity, absolutely nothing happens
because of the V/I ratio.

The last half of the sentence is absolute correct. The V/I ratio is a
result, not a cause.

73, ac6xg

Revisiting the Power Explanation
 

On Apr 2, 1:51 pm, Richard Clark wrote:
On Sun, 01 Apr 2007 18:30:06 GMT, Cecil Moore
wrote:

Cecil Moore wrote:

Richard, did you unethically edit my posting to make
it appear that I said something different from what
I said?

So, are you still sleeping with Hecht?

Richard, it's very uncommon, but on this issue I'm having a difficult
time following you. The only reason that I can conclude for my lack of
understanding is that our definition of 'interference' must be
divergent. So I'll just drop the discussion--OK?

Walt

Revisiting the Power Explanation
 

On Mar 31, 6:01 pm, Cecil Moore wrote:

In the following fixed font diagram, IR is the Index
of Refraction.

IR usually means 'infra red' in optics discussions. The letter 'n' is
customarily used for the variable representing index of refraction.
Sort of obviates the need to define one in every discussion.

air | 1/4WL thin-film | Glass
1W Laser---IR=1.0---|----IR=1.222-----|--IR=1.493---...
Ifor=1W | Ifor=1.0101W | Ifor=1W
Iref=0W | Iref=0.0101W | Iref=0

Note that I is "irradiance", not current.

Also note that 'Watt' isn't a unit of irradiance or current.

73, ac6xg

Revisiting the Power Explanation
 

On Mar 28, 7:38 pm, Cecil Moore wrote:
Keith Dysart wrote:
Once again the hypothetical equality
Preflected = Pdissipated + Pre-reflected
229.6 = 872 + 0
does not hold.

I have pointed out your errors and misconceptions
3-4 times and you have refused to correct them.
This is the last time I am going to waste my
time.

The source is a 2A Norton with a shunt 450 ohm
resistor. During steady-state, the source sees
75 ohms. Adding 1WL of 75 ohm lossless line doesn't
change anything but for the Nth time, points out
your errors and misconceptions.

source--1WL 75 ohm line--+--1000' 450 ohm line--75 ohm load
Pfor1-- Pfor2-- Pload
--Pref1 --Pref2

Taking your numbers, Pload = 220.4w, Pfor2 = 450w, and
Pref2 = 229.6w

Obviously Pfor1 = Pload = 220.4w and Pref1 = ZERO

The joules/sec into the impedance discontinuity must equal
the joules/sec out of the impedance discontinuity. Let's
see if they do.
Pfor1 + Pref2 = Pref1 + Pfor2
220.4 + 229.6 = ZERO + 450
450 joules/sec = 450 joules/sec

There you have it. You simply made a mistake. There is NO
violation of the conservation of energy principle. The
same conditions that exist at the impedance discontinuity
also exist at the source. Total destructive interference
toward the source is accompanied by total constructive
interference toward the load. Every sliver of energy is
accounted for. You analysis is, once again, simply wrong.
--
73, Cecil http://www.w5dxp.com

I didn't catch this first time round, but better late then never.

As you say, adding 1 wavelength of 75 Ohm line will not change
the steady state.

So the condition on the right side of the inserted 75 Ohm line
section will be reproduced on the left side of the line section.

This means that reflecting back into the generator from the
left end of the 75 Ohm line will be the same Pref2 = 229.6 W
that exists on the right side of the 75 Ohm line section.

If you doubt, do the same energy analysis for the left end of
the line that you did for the right end. The generator is
putting 450 W forward into the connection to the 75 Ohm line,
229.6 W is being reflected and 220.4 W is entering the 75 Ohm
line. All is in balance at the connection at the left end
as it is at the right end. But 229.6 W are going back into
the generator. Where do these Watts go?

Using your analytical approach it may help if you put a one
wavelength section of 450 Ohm line between the generator
and the 75 Ohm line section previously inserted. This will
not change the steady state result but may make it easier
to visualize the reflected 229.6 W.

....Keith

Revisiting the Power Explanation
 

On Sun, 01 Apr 2007 16:43:01 GMT, Walter Maxwell
wrote:

Richard, are you avoiding answering my question because you don't want to admit that the null in an antenna
pattern results from interference between two coherent fields?

Hi Walt,

Of course a null, or a peak, or any point in between results in the
interference (the combination of energy phases as power from separate
sources, or separate waves) found only in a load. I recall having
posted comments specifically to the issue of phase combination several
many times in as many days. I will do it several times more he

That same point in space without that load has absolutely no effect on
any energies that passes through it. Energies do not mix (combine) in
linear space; thus one energy can have no effect on other energies.
Any single energy is unperturbed by any other energies without that
load to offer a point of summation (the point of interference). That
unloaded point in space cannot support reflections or force any change
on any energy.

Interference is not the cessation of energy flow; it is not an
impediment to energy flow; it is not an redirection of energy flow; it
is not the amplification of energy flow; it is merely the passive
observation at a point of the summation in a load of all contributions
of energy flow. Further, the load may compound the redistribution of
energy flows (AKA directors or reflectors) becoming, as it were, a new
and separate source for a yet another remote load to combine new phase
relationships into a new null/peak/what-have-you. Remove the load,
and those products disappear.

Interference follows the load. Interference is caused by source
relationships developed at the load. Move ANY of these actors, and
the entire map of responsivity changes. All antenna graphical lobe
descriptions demonstrate this.

73's
Richard Clark, KB7QHC

Revisiting the Power Explanation
 

On Sun, 01 Apr 2007 19:04:49 GMT, Walter Maxwell
wrote:

Allright, Richard, then where is the load when there are two vertical radiators spaced 1/4 wl and fed in
quadrature, such that their individual fields are omni-directional in azimuth, but when the two fields
combine, a maximum greater than either of the individual fields is propagated in one direction, while a null
results in the opposite direction, negating the propagation of the individual fields in the direction of the
null. What is your explanation of the negation of the propagation of the individual fields when both radiators
are radiating equal EM energy? Are you still denying that interference is not the cause of the modification of
the resultant fields? So I repeat the question--where is the load in this case?

Hi Walt,

The load is anywhere you place it, obviously. We can even abstract
one radiator of these two radiators being a load for the other - and
through symmetry, the other way around. They obviously interefere
with each other. As I've offered, remove (or simply move) either and
the entire picture changes. If you want to add yet another, remote
load, that is fine. There is no limit to where it can reside. There
is no limit in the number of loads either. All loads reveal
interference, however, if you remove them, obviously there is no
interference.

Fields do not act one upon the other in linear space. The addition of
a load may present a new source of radiation. In that case, the new
mapping of wave action follows the load. This is demonstrated in
every yagi. Remove the load (or yagi element) and the specific
mapping changes, following the load.

73's
Richard Clark, KB7QHC