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Re: [TowerTalk] matching to screwdriver antennas

To: "Jim Lux" <>, <>
Subject: Re: [TowerTalk] matching to screwdriver antennas
From: "Tom Rauch" <>
Reply-to: Tom Rauch <>
Date: Thu, 3 Jun 2004 05:20:12 -0400
List-post: <>
>> One approach that has been used is to use a 4:1 (or other
ratio, as
> suitable) transformer, with capacitive coupling between
primary and
> secondary (either parasitic, or explicit). The idea is
that as the frequency
> goes up, the capacitance tends to dominate over the
transformer.  At low
> frequencies, the impedance of the capacitor is high enough
that it is
> irrelevant.

I'm missing something Jim.

How does the transformer decrease magnetic mutual coupling
effects from primary to secondary as it increases "bypass"
capacitance to effectively reduce turns ratio with
increasing frequency?

All I see happening is it making the system reactive while
the effective ratio barely changes if flux coupling is high.

73 Tom


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