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An antenna question--43 ft vertical
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July 6th 15, 05:53 PM posted to rec.radio.amateur.antenna
John S
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First recorded activity by RadioBanter: May 2011
Posts: 550
An antenna question--43 ft vertical
On 7/6/2015 11:44 AM,
wrote:
Ian Jackson wrote:
In message , rickman
writes
How about we quit with the speculation and come up with some numbers?
Here is a simulation of a 50 ohm load with a 50 ohm matched series
output impedance and a voltage source of 200 VAC peak. Power into the
load is 100 W.
http://arius.com/sims/Matched%20Load%20Power.png
Same exact circuit with the series impedance of just 1 ohm, power into
the load is 385 W.
http://arius.com/sims/UnMatched%20Load%20Power.png
I'd say that is pretty clear evidence that matched loads are not the
way to maximize power transfer when the load impedance is fixed and the
output impedance is controllable.
Quite simply, if your prime objective is to get maximum power out of a
power (energy?) source, the source having an internal resistance is a
BAD THING. You don't design the source to have an internal resistance
equal to its intended load resistance. No one designs lead-acid
batteries that way (do they?), so why RF transmitters?
Because RF transmitters deliver high frequency AC to a transmission line.
So, the laws of physics are different with AC (high frequency or not)?
Please show the equations, literature, links, or any other suitable
authority advancing that theory.
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