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Old May 4th 10, 12:51 AM posted to rec.radio.amateur.antenna
lu6etj lu6etj is offline
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First recorded activity by RadioBanter: Jul 2006
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On 3 mayo, 19:35, Roy Lewallen wrote:
lu6etj wrote:

No, no :) both wires are introduced in each driven element tubes, at
similar mode as a coaxial cable stripped of braid is introduced in a
gamma rod.


It's not obvious how you'd be able to effect an impedance match with
this method. To be able to match an arbitrary impedance, you need to be
able to adjust two things which are at least partially independent. For
example, a gamma rod length and series capacitance. With this scheme,
you've got the length of the wires inserted in the tubes. What else can
you adjust? Wire diameter will give you some variability, but not an
awful lot, and it isn't easy to vary.

Roy Lewallen, W7EL


Thanks Roy (and Ian). Well... I thought the same thing that you and
that it is the reason of my question. Several times I heard of it and
for that reason I wanted to look for information in the Net to find
some possible explanation. I remember that years ago I neither
understood very well how the double bazooka worked :)

MIguel Ghezzi LU 6ETJ