The signal which goes down the feedline depends on the losses incurred in
the system, by design, feeder type, or "resonance" etc. ( and that is a
topic in itself....) if the feeders for example are as lossless as you can
make them,
(i.e; heavy duty open wire feeders,) the signal loss will be as minimal as
you can make it. Sure the tuner, (balanced or otherwise) will incurr losses
again, but most of the time these losses are so miniscule, that I defy
anyone to note the difference...
An enormous mismatch is not a problem ( with tuned feeders, as they are not
so lossy) if you can match the load to the rig, and providing your atu
design is sound. Do things get worse?? Sure.... but ever so slightly... so
much so it doesn't matter.... it's a different case when you have a run of
about 100 foot of RG 58 ..coax.. yeap then there are heaps of losses, and
the feed line is radiating like crazy....
Feedpoint matching is not always convenient...especially for multiband
use..(i.e.: The typical zepp antenna, with tuned feeders) The antenna has
been around a long time, it works, and will be here for a long while to
come. The proof is in the pudding. The design of this "pudding" confirms the
above.
Better proof of this pudding is in the eating.
I have compared on 40mx, the dx performance of a dipole feed with tuned
feeders at the shack end, and a dipole at the same height matched at the
feedpoint with a current balun. The results were exactly the same, as one
would expect. There ia a big bonus for the zepp in that it is usable at
other fequencies, with little loss incurred.
Enjoying the reflector.
Maurie VK3CWB.
" I have never tuned a fish... but I have tuned a tree, and a railway line!"
--
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