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Old June 1st 04, 03:36 PM
Wes Stewart
 
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On Tue, 1 Jun 2004 10:11:14 +0100, "Richard"
wrote:

|
|"Wes Stewart" wrote in message
.. .
| On Mon, 31 May 2004 15:59:31 +0100, "Richard"
| wrote:
|
| |I'm just about getting around to making my 5 or 6 element marine band
|yagi,
| |covering 156 - 162 Mhz RECEIVE ONLY. Do I have to employ a folded dipole
|
| No.
|
| |or
| |can I use just a simple hertz dipole as the "driven" element? I'm trying
|to
| |get away from using a folded dipole if I can. Any wideband designs out
|there
| |that use a simple hertz dipole that I can scale? I'm looking, but if you
| |have some links aready. TIA.
|
| All dimensions in inches
|
| X Y Z X Y Z Dia
|
| 0.000 -18.553 0.000 0.000 18.553 0.000 0.187
| 9.275 -18.368 0.000 9.275 18.368 0.000 0.312
| 12.250 -17.077 0.000 12.250 17.077 0.000 0.187
| 23.800 -16.672 0.000 23.800 16.672 0.000 0.187
| 34.213 -16.672 0.000 34.213 16.672 0.000 0.187
| 47.211 -16.229 0.000 47.211 16.229 0.000 0.187
|
|
|Sorry I'm a bit uncertain of what you wrote.
|
|Obviously an efficient way to provide data for yagi's, but how do you read
|it?
|
|Is there a webpage associated with the design, so I can look at the general
|construction?
|
|Rich.

This is the format for almost any of the common antenna modeling
programs. See for example:

Free:

http://www.qsl.net/wb6tpu/swindex.html (look for files beginning
4nec2)

Almost free:

http://www.qsl.net/ac6la/multinec.html

Free demo:

www.eznec.com

etc.

With a fixed width font, the columns would line up and each line would
represent one element, starting from the rear (reflector end) of the
boom. The data are the X,Y,Z coordinates of the ends of the elements
and the diameter of that element. Z is this case is zero since the
model assumes free space. It also assumes no effects from the
supporting boom; the usual compensations must be made for this,
depending on the element mounting method. See:

http://www.antennspecialisten.se/en/ham/tech/bc.html

I assumed that you had some experience with Yagi design and
construction and were simply looking for a design that gave both the
required bandwidth and a fifty-ohm feedpoint; something this design
delivers.