Probably was in about 1957 QST the little ditty appeared:
Feeders going up the wall,
Please don't radiate at all.
For if you do, then by and by,
I'll be plagued with TVI.
author unknown by me
N4NT
----- Original Message -----
From: "Stuart Rohre" <rohre@arlut.utexas.edu>
To: "Discussion of Ten-Tec Equipment" <tentec@contesting.com>;
<wb2vuf@qsl.net>
Sent: Friday, July 08, 2005 3:13 PM
Subject: Re: [TenTec] "Radiates like Crazy"???? No
I must respectfully disagree that ladder line "radiates like crazy".
It is BALANCED line, that means if it is fed from a balanced source and goes
to a balanced antenna, the currents are equal and opposite in each wire and
their fields cancel within a few diameters of the line. See the theory of
transmission lines in the ARRL Handbooks.
It should cross conductors at right angles, and should be twisted every 18
inches or so, to minimize effects from nearby conductors that could
unbalance it.
If you ever have ladder line "radiating" you are mis applying it in some way
at one end or the other. Balanced antennas are center fed beams, dipoles,
etc. with line brought off at 90 degrees to the antenna wires.
Let's bury these old wive's tales about balanced parallel transmission
lines.
Stuart
K5KVH
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