All true of course. I had taken for granted that the line was considered
to be properly terminated at both ends, or else "infinite" in length.
These of course are the only conditions to which the classic theory
applies. If you mis-apply the line, it won't work right :)
73 de Gary, AA2IZ
Ok.... I promise not to post any more to this thread. Its getting a little
worn. :)
----- Original Message -----
From: "Cliff" <csegar@mindspring.com>
To: "Rob Atkinson, K5UJ" <k5uj@hotmail.com>
Cc: <tentec@contesting.com>
Sent: Wednesday, October 16, 2002 9:50 AM
Subject: Re: [TenTec] TWINCOM feed line ?????????????
> Well, we've certainly seen a lot of opinions now about open (parallel)
wire
> feed line and how it radiates. What you really need to ask yourself is
> "what is the characteristic impedance of the radiating device at the
> desired frequency of operation."
> Any feed line will become part of the antenna system (radiate) if it is
not
> matched to the impedance of the source (transmitter) and load (antenna).
> Also consider whether the antenna is balanced or unbalanced. Open wire is
> balanced whereas coaxial transmission lines are unbalanced. Feeding a
> dipole with the best quality LDF7-50 will result in RF radiating from the
> feed line. Feeding a 1/4 wave vertical with the best 450 ohm open wire
> available from "The Wireman" will result in RF radiating from the feed
line.
> Using the proper feed line (via baluns if necessary) to a resonant antenna
> will result in happy finals in the transmitter, higher signal strength on
> the receiver and less TVI/RFI to the neighbors.
> Long live 50 j0
>
> 73 de KD4GT
>
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