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Old July 3rd 11, 12:24 AM posted to rec.radio.amateur.antenna
Michael[_10_] Michael[_10_] is offline
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First recorded activity by RadioBanter: Aug 2009
Posts: 28
Default Does anyone have plans for a 4:1 air core balun that actually works?

On Jul 2, 7:05*pm, Owen Duffy wrote:
Michael wrote :
...

* So how do I go about feeding a Lazy H with ladder line back to the
tuner for high power without over heating the balun? *The tuner is a
Dentron MT-3000a. *The built in balun is not balanced at all at 10


I will respond in a couple of hours, but in the meantime, please clarify
that everything between the ATU and LazyH is up for consideration.

What impedance line are you using?

Do you feed the antenna midway between the elements of at one element
(branch or distributed feed)? What do you think the feed point impedance
is?

What band(s)?

Owen


I am using 450 ladder line. The Lazy H is center fed with 1/2 wave
spacing between the top and bottom elements and the elements are 1/2
wave elements. 450 ladder line is connecting the top and bottom
elements. I am not using the expanded Lazy H version. This is the
classic center fed Lazy H design as shown in the ARRL antenna
handbook. I only intend to use the antenna on 10 meters. I don't
know what the exact impedance is (sorry). The Lazy antenna is about
50 feet off the ground at the top wire. The amplifier I want to use
with the Lazy H is a Drake L4B with two Eimac 3-500z tubes.

Michael Rawls
KS4HY