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Old November 26th 09, 08:20 AM
hamradiolocator hamradiolocator is offline
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First recorded activity by RadioBanter: Nov 2009
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Quote:
Originally Posted by Dave Platt View Post
Suppose we feed 20 watts in a p.a. but don't want to use a dummyload
in the p.a. Come on this is done all the time.


Sure. If one does not want to have a dummy load in the PA, one uses
an *external* dummy load.

A dummy load, almost by definition, is something which accepts RF, and
dissipates it as heat. An ideal dummy load doesn't radiate at all. If
it does radiate significantly, we call it an "antenna".

One *cannot* magically make those 20 watts disappear. They either
have to be radiated (out into space) or converted to heat and
dissipated.

A small LC circuit will not do a good job of either of these things...
won't radiate efficiently and won't have enough resistance to act as a
comfortable dummy load (e.g. Zo near 50+0j).

--
Dave Platt AE6EO
Friends of Jade Warrior home page:
http://www.radagast.org/jade-warrior
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It's a bit hard to see, but it looks like the feed (left to right in the
picture) is to the 2nd element with a crossed phase parallel line to the
third.