Thread: Dish reflector
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Old May 1st 09, 11:19 PM posted to rec.radio.amateur.antenna
Art Unwin Art Unwin is offline
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First recorded activity by RadioBanter: Mar 2008
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Default Dish reflector

On May 1, 3:55*pm, Cecil Moore wrote:
Jim Kelley wrote:
Cecil Moore wrote:


We would make a measurement of either the forward or the reflected
traveling wave, which are phase delayed along the antenna.


I'm sorry, but that is a false statement. Measuring the forward
or reflected traveling wave, which is less than 10% of the
total energy *on the antenna*, is exactly what is the problem.


Hmmmm. *Perhaps I misspoke. *I should have said that's what I usually
measure when I want to know how much power my antenna is radiating. *I
guess I don't actually know for sure what other people usually measure.
But if they have a Bird wattmeter for example, that's what they usually
measure too.


The context, as proved by your first posting above is
measurements "along the antenna". Why do you need to divert
the issue by changing the context in midstream? Why can't
you just discuss things in context?

A Bird wattmeter will not work "along the antenna". Contrary
to what you assert above, *nobody* uses a Bird wattmeter
"along the antenna" to measure anything. A Bird wattmeter
is a 4-terminal device requiring a reference which doesn't
exist "along the antenna".

The only measurements that have been made "along the antenna"
are total current measurements. Seems the only way to measure
forward traveling waves "along the antenna" is to use a
traveling wave antenna like a terminated rhombic.
--
73, Cecil, IEEE, OOTC, *http://www.w5dxp.com


I think that is pretty accurate Cecil.
Richard took to argueing with Dr Davis working at MIT
where he argued that the Laws of Maxwell do not equate mathematically
to the laws of other masters.He was speaking in his normal Olde
English term which is talking instead of communicating until he drove
the good Doctor away in fraustration.
Richard took that as a victory for Shakesphere over the degree in
mathematics that
Dr Davis earned. Richard now believes he has advanced in the pecking
order in matters relating to Radio no less.