J pole question
On 10/13/10 1:14 PM, Owen Duffy wrote:
Mike wrote in :
The big question I have always had regarding the balun was are we
reducing performance by eliminating feedline radiation? For a lot of
antennas, that may be a big part of the antenna system.
Claiming feed line contribution to radiation as a performance factor is
usually a specious claim, and more likely to be made by someone with a
commercial imperative than a genuine interest in radiation performance. You
know, if you can't solve a problem characteristic, call it out as a
feature.
I don't disagree, but certain antennas - the EH antenna comes to mind,
which resemble a tuned circuit on a stick. Get rid of the feed line
radiation, and you almost get rid of the whole antenna. But like you
say, its a "feature".
It's also not good practice.
In this case, feed line radiation would usually skew the pattern upwards,
not necessarily a desirable feature, probably not desirable in most
situations.
Not too desirable. Thanks for the clarification. Mine was a general sort
of response, not limited to this antenna.
- 73 de Mike N3LI -
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