Towertalk
[Top] [All Lists]

Re: [TowerTalk] matching to screwdriver antennas

To: "Jim Lux" <jimlux@earthlink.net>, <towertalk@contesting.com>
Subject: Re: [TowerTalk] matching to screwdriver antennas
From: "Tom Rauch" <w8ji@contesting.com>
Reply-to: Tom Rauch <w8ji@contesting.com>
Date: Thu, 3 Jun 2004 05:20:12 -0400
List-post: <mailto:towertalk@contesting.com>
>> 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


_______________________________________________

See: http://www.mscomputer.com  for "Self Supporting Towers", "Wireless Weather 
Stations", and lot's more.  Call Toll Free, 1-800-333-9041 with any questions 
and ask for Sherman, W2FLA.

_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk

<Prev in Thread] Current Thread [Next in Thread>