Jerry can deal with this at whatever level he chooses, but the short answer
is that parallel lines do NOT radiate precisely because they are close
enough in terms of wavelength for their equal and opposite fields to
essentially cancel.
As the lines are moved further apart, the "field strength volume" they
share decreases as does the degree of cancellation. Eventually you have two
wires far enough removed that they exert little or no effect on one
another. And thus radiation occurs from each in the manner of an antenna.
In fact, if you take a parallel-line transmission line and feed it at one
end and then start spreading the wires apart until they are separated by
180 deg, you have a dipole. And they radiate quite well . . . <:}
Visualize an open-wire line with five-foot spacing being used on two meters
. . .
73/72, George
Amateur Radio W5YR - the Yellow Rose of Texas
In the 57th year and it just keeps getting better!
Fairview, TX 30 mi NE of Dallas in Collin county EM13qe
K2 #489 Icom IC-765 #2349 Icom IC-756 PRO #2121
Gary Hoffman wrote:
>
> Why would a wider spaced feed line radiate more ? It should not
> radiate at all, unless you are assuming there is unbalance, or poor
> construction. But, given proper implementation, it should radiate nothing.
>
> 73 de Gary, AA2IZ
>
> ----- Original Message -----
> From: "Dr. Gerald N. Johnson, electrical engineer" <geraldj@isunet.net>
> To: "Rob Atkinson, K5UJ" <k5uj@hotmail.com>
> Cc: <tentec@contesting.com>
> Sent: Tuesday, October 15, 2002 1:54 PM
> Subject: Re: [TenTec] TWINCOM feedline ?????????????
>
> > The wider the space the more the feed line radiates.
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