Re: Revisiting the Power Explanation

On Sun, 01 Apr 2007 02:44:04 GMT, Walter Maxwell <walt@xxxxxxxx> wrote:

On Sat, 31 Mar 2007 18:01:53 -0800, Richard Clark <kb7qhc@xxxxxxxxxxx> wrote:

On Sat, 31 Mar 2007 19:16:23 GMT, Walter Maxwell <walt@xxxxxxxx>
wrote:
snip
There is absolutely no example of interference that does not rely on a
load to reveal it.

If what you just said is true, then how do you explain nulls in a radiation pattern of an antenna having more
than one radiator, for example two verticals spaced 1/4 wl and fed in quadrature, thus creating a cardioid
pattern with a total null in one direction in azimuth? If the null was not created by interference between the
radiations from the two verticals, then how do you explain the formation of the null?

I use a load. It is exactly like the internal resistance of a
internal resistance where the reflected energy is in phase with the
source. The load exhibits no current flow (a null). Shift the phase
180 and the internal resistance exhibits a dramatic current flow (a
lobe). The energies are there either way. Remove the internal
resistance and nothing conducts EVER. Clearly the internal resistance
(the load in this case) is what reveals interference, not the
energies. In free space they would pass like ships in the night.

73's
Richard Clark, KB7QHC

Richard, you are dodging the question again! You have not answered my question, 'how do you explain the
formation of the null in an antenna pattern' in the example I presented above?

Walt

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?

Walt
.

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