> Why do we have to build something as
> complicated as a matching transformer instead of a tuner? 73
> Tom W7WHY
Hi Tom,
first of all a simple transformer is finally much simpler than a tuner,
it's broad band, the coupling is primarily magnetical, the unit is self
shielded and the required enclosure is quite small. All this allows
that the transformer unit is easily placed at the antenna end, and
grounded, avoiding that a feed line acts as an antenna picking up from
unwanted directions or that the antenna has to begin close to a tuner
(generally close or inside the shack) so receiving all the domestic
noises (appliances, computers etc.)
Second, the beverage is inherently a non resonant antenna whose best
match is obtained when the SWR is flat, not necessarily it has (or it
can be) a 1:1 SWR. Matching for 1:1 with a tuner a piece of wire,
expecially if unterminated, there is the consistent risk to obtain an
antenna that doesn't behave much like a beverage.
73,
Mauri I4JMY
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