I was asked why 90 feet of 300 ohm ladder line by the group. Ron of DX
Engineering responds below.
Philip LaMarche
LaMarche Enterprises, Inc.
www.instantgourmetspices.com
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You can go straight to www.W2DU.com to get thePDF's.
Russ, N3CO
- Forwarded Message
From: Joe Planisky
To: Elecraft Reflector
Sent: Wednesday, July 15, 2009 10:28:32 PM
Subject: Re: [Elecraft] The use of a doublet
For those who might be a little mystified by this discussion ofÂ
fee
In the Book one studies for the Amateur Extra book are tables of what occurs
to voltage and current in the feedline. The graphed waves of voltage and
current in the feedline are different for coax compared to ladder line. The
graphs have tick marks every 1/4 wavelength of the frequency in use -
Tnx Phil.
Note that using the lengths do not improve the performance, only the
impedance excursions involved and they can be handled by a wide range tuner
quite nicely.
That said, some tuners show excessive losses at extreme impedances even
though they may show a 1:1 SWR on the coax link to the
Phil,
Ron speaks truth!
The "magic" is that the feedline acts as an impedance transformer, and
open wire line (or dry twinlead) will operate at high SWRs with
negligible loss.
We have formulas for quarterwave (or odd multiple) transmission line
sections, but not often mentioned is that the tra
--- On Tue, 7/14/09, Ron D'Eau Claire wrote:
Note that using the lengths do not improve the performance, only the
impedance excursions involved and they can be handled by a wide range tuner
quite nicely.
That said, some tuners show excessive losses at extreme impedances even
though they may sho
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