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Subject: PS Was Force 12 Verticals
Author: bjk@ihug.co.nz <bjk@ihug.co.nz>
Date: 13-Oct-2002 22:51:22
Value engineering can be a useful approach to decisions about developing an hf
amateur radio station.

The classic reference is ?Rockwell "Station Design for DX. ca 1960. ARRL should stir
itself and commission and up to date version.
Another source I found useful was a series on HF DX by the RSGB around 1995 where
they surveyed leading UK DX operators.
Rockwell took the approach of looking at DX dB per dollar.

In the matter of antennas for 14-30 mHz the finding was that around 40-45 feet gave the
best cost vs benefit. Below this radiation angles are too high, above this costs escalate.
Antenna mdelling programs will show the truth of this.

The UK top ops had 40ft with a trap tribander as the most common set up.

If using a light compact beam (such as the F12 C family) then inexpensive pipe masts
can get up 40-45 feet, cheap.

In the old Ham Radio magazine K6? did field studies comparing quads and yagis 14-
30mHz against a reference two element trap dipole at the same site at the samer site.
Gain figures for the trap dipoles across any band were a bit sad, indeed the two element
job compared very favourably with the big ones. Of course the tribanders gave
directivity on receive and so improved overall station capability, but did not compare
well with a dipole on most frequencies.

The F12 propaganda is true, folks!

Given a C family antenna at 40-45 feet and a reasonable transceiver and amp at the
bottom one really has an effective radio station by any standard, where operator nous
and skill will give more advantages than a heap more money spent on hardware,
assuming a reasonable location.

Do not be hypnotised by the super stations. Add a F12 rotary dipole to the above and
fire up the mast against ground radials for 80 and one has a seriously effective station,
able to work almost anything it can hear even in the presence of competition. (A
dedicated receive antenna for 80 can be a good secret weapon).
73
Barry ZL1DD




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This Thread
  Date   Author  
14-Oct-2002 Allan Henry Kaplan
14-Oct-2002 D C Macdonald
14-Oct-2002 Joe Mitchell
14-Oct-2002 Pete Smith
14-Oct-2002 Pete Smith
* 13-Oct-2002 bjk@ihug.co.nz
This Author (Oct-2002)
  Subject   Date  
* PS Was Force 12 Verticals 13-Oct-2002