A couple of observations:
1) It would benefit from an effective ferrite-cored choke balun at the
input rather than the narrowband air-cored balun that he suggests.
2) Apart from the balun, the CM performance is critically dependent on
symmetrical construction of the matching components. If you force
current balance at the input using the balun, but then have asymmetry in
the following matching components, you will guarantee asymmetrical
currents at the output terminals. The very worst example I have seen of
this is the Palstar BT1500A where on the higher frequency bands they
switch out most of the rotor vanes but leave the static vanes in circuit
and close to the chassis!!!! As you might imagine the CM impedance turns
out to be mediocre.
Steve G3TXQ
On 19/07/2016 13:22, Steve Elliston wrote:
do we like:
"A *Balanced* Balanced Antenna Tuner
By Richard L. Measures, AG6K
The published version of this article appeared in the February 1990 issue
of QST Magazine." ?
73
Steve
G3XKR
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