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Old September 7th 10, 07:43 AM posted to rec.radio.shortwave
John Smith John Smith is offline
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On 9/6/2010 5:44 PM, John Smith wrote:


This is even an improvement over the more common baluns you find around.
The balun show is a 4:1, consisting of two bifilar windings, one
bifilar on each side of a single toroid. It is shown in Fig. 4 and text
describes its' construction and working. There is even a graph showing
performance across a wide bandwidth. This design can be expanded to a
9:1 by simply using two trifilar windings in place of the two bifilar
windings, and making proper connection of the windings.

http://www.home.earthlink.net/~chris...k4to1Balun.pdf

I suspect a gain in performance would be had with most, if not all,
antennas in common use. And, as the text points out, grounding the
correct side of the secondary series windings will allow the balun to be
used as an UNUN.

Regards,
JS