[Antennas] From transmission lines to tuners

[A10382]

A few years ago, ARRL did a review of a few tuners... and included the
losses measured at each band in the process of tuning out system impedance
mismatches.  Many readers were astonished at how much can be lost in the
tuner's effort to make the antenna system more 'transmitter friendly' (read:
impedance matched).

The rf power leaving the transmitter's finals ( or those of the amp) has to
go somewhere:

1) Radiated from something in the system (including feedline radiation
inside and outside)
2) Lost as heat anywhere in the whole system (Hmmm.. wonder why the outside
part of the system never ices up ??  Wonder why the antenna balun never ices
up ??)
3) to ground

While it's impossible to have true 100% efficiency, the tuners tested had
losses as high as 60% on some bands -- and these were the 'better quality'
tuners.

Frank
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 ._._.
----- Original Message -----
From: "Pat W" <w0opw@yahoo.com>
To: <antennas@mailman.qth.net>
Sent: Thursday, December 19, 2002 12:08 PM
Subject: Re: [Antennas] From transmission lines to tuners


> The whole subject gets complicated really fast.  My
> best guess is that an SWR of < 1.5:1 at the tuner side
> will have more loss in the tuner trying to tune it out.
>
>  I started to give a presentation at my local Ham Radio
> club on this subject but it got bogged down in a hurry.
>
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