While I am a devoted fan of Ten Tec gear, I will not recommend their tuners as
being the "best" design for use with open wire
transmission lines. This is because it is my understanding that the design is
a basic T type L C network. This is fine for
unbalanced line but not balanced. The solution the factory uses is to place a
balun in the output of the tuner. While this may
work just fine into a perfect impediance match, it defeats the purpose of using
open wire line. That is to obtain tremendous
bandwith and very high efficiency by using a properly designed antenna tuner
that has true balanced output. An example of this
design is the old Johnson Matchbox and many examples of this type are shown in
the ARRL Antenna Book and Handbook. It is common
knowledge that high reflected power will cause an iron core balun to "saturate"
and generate heat from the precious reflected power,
thereby wasting power. A much better method for feeding open wire line is to
place the ba!
lun on the input side of the T type tuner. Why this simple solution never
occured to the factory seems odd? However, I understand
that there is one company that does make an antenna tuner with the balun on the
input side, specifically for feeding open wire line.
Seems like Ten Tec could do the same for very small, if any cost. - Sherrill
W. k4own
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