It would be interesting to compare the FCP against a wire mesh on the ground at
the base to 30-50' out in 4-5 spokes as Ive described several times. That made
all the difference in the world when 60 or so on ground radials had been
several tiers down with 600 and then 1200W into a 100' shunt fed tower with a
4el 20-10M Christmas tree for top loading, it was resonant somewhere in the
1400-1500KHz region, forget exactly where.
The mesh was standard garden store 2X4" welded, then hot dip galvanized and
plastic coated "rabbit fence" as they call it up here.
I connected the spokes together in many places after laying them on top of the
insulated wire radials, ran a perimeter wire and attached the existing radials
to that.I suspect the radials didnt add much to the signal since the ground was
pure sand right down to the fresh water table.
Carl
KM1H
----- Original Message -----
From: Guy Olinger K2AV
To: ZR
Cc: Topband@contesting.com
Sent: Friday, August 31, 2012 6:51 PM
Subject: Re: Topband: Small antenna book
Hi Carl,
Short version: The problem was never the wire in the air. Problem was the
counterpoise. We'll see what Grant has to offer.
Long version:
I've ordered the book.
I'm sure that the OT's got on the band with quite a variety of setups. I was
there when young and reckless, and saw some doozies. We did some really
dangerous things back then. Question is how efficient those were. We burned
up stuff.
I don't think anyone ever solved counterpoise in small places for 160, other
than for high impedance feeds where the effective series resistance of a
minimalist "ground system" simply didn't matter. ON4UN's 4 x 1/8 wave elevated
is the closest anyone came to "small" that really works until now. My 80
meter end-fed half wave against a couple of buried 40 foot bare copper wires
took advantage of a very high Z feed, and worked extremely well.
Small lotters were always compromised on the shield side of the coax, even if
they got clever with the radiator. There is a reason for the seven to ten dB
jump that some folks have experienced moving to an FCP. Most of the power was
being dumped into the dirt, one way or another, by a seriously compromised
radial scheme. Some of these changes involved no change to the vertical
radiator other than adding a few percent to something already about 1/4 wave
already to re-prune for resonance. Yanked all the radials, put up the FCP,
kept the same wire upstairs, and bingo. It wasn't the wire in the air that was
the problem, it was the "radials".
I'm one of those who got on 160 with a real signal because of an FCP. I
don't have anywhere on my property I could place anything that would even
remotely meet the description of full size dense and uniform all around. My
lot is long and skinny, with the driveway dividing the property going out to
the US 64 service road.
When I decided to get on 160 here, I asked around for some advice. Advice I
got was to try two opposed 1/4 wave radials on the ground, with whatever
shorter radials I could add. This was in the same time frame W3LPL was
installing two raised 1/4 w radials for each of the verticals in his new four
square. Two opposed was the hot advice then.
I could get two pretty much opposed 1/4 wave radials on the ground near the
eastern N/S property line plus miscellaneous shorter ones and get a 1/4 wave L
over it. That clearly did not get out well. With the amp in line, when I
asked a friend in New Mexico about my signal, he politely replied "You're
really not very loud." Then later he called W4MYA "a beacon". The distinction
was not lost on me. He didn't tell it to me in dB, but I know from his long
acquaintance that the difference between his "not very loud" and "beacon" is a
collection of S units.
And it confirmed my general experience. With those radials down, it took an
amp to compete with others running 100 watts, and I wasn't doing all that well
with the amp. I could work some countries on 160, but only after the pileup
had died down. I was obviously down in the fourth and fifth tier in contests.
I WAS having fun on 160, but wished to high heaven I could have A SIGNAL.
I have earned the right to call two opposed 1/4 wave radials a sh*t solution
to counterpoise, nowhere near the performance of a commercial radial field some
of the fellows around here were using.
The issue now is to get solutions out there so that small lotters can play in
the same game with the big guys and make them sweat the results, solutions good
enough to hold a run frequency in a 160m contest running 100 watts.
73, Guy.
On Fri, Aug 31, 2012 at 3:46 PM, ZR <zr@jeremy.mv.com> wrote:
Id like to think that many of the OT's that worked the band under the old
power restrictions found many suitable small lot antennas.
A look thru the old QST's, CQ, Radio, HRM, etc likely will show a few.
In the 50's I used a 80M dipole fed with 72 Ohm twinlead tied together at
the rig on 160; the Johnson Viking I loaded it and I made many contacts
including AM mobiles.
In the 60's I used what would later be called a half sloper and in the 80's
I worked coast to coast with 100W to a 750' Beverage just for grins and giggles
to see if it was possible after reading a QST artcle about the Canadian
government using an array for a ZL link on a higher frequency. It was reported
as more reliable than conventional antennas.
Carl
KM1H
----- Original Message ----- From: "Guy Olinger K2AV"
<olinger@bellsouth.net>
To: "Paul Christensen" <w9ac@arrl.net>
Cc: <Topband@contesting.com>
Sent: Friday, August 31, 2012 9:35 AM
Subject: Re: Topband: Small antenna book
I'll wait to comment until I've had a chance to read the book and see
what's really in it, what kind of built and tried in contest experience,
etc, and how it applies. 20 bux from ARRL plus shipping.
ANY contribution to the pitiful state of 160 know-how for the small-lotter
is welcomed. I'll support the guy with a book purchase just because he
was THINKING about the little guy on 160.
2012 :>) 75 years since Brown, Lewis and Epstein. Jeeze.
Like the FCP, all this should have been out there when they turned off the
LORAN. What were they thinking.
73, Guy.
On Thu, Aug 30, 2012 at 7:13 PM, Paul Christensen <w9ac@arrl.net> wrote:
On the surface this seems to agree with what I find. There are dozens
of
ways to have about the same results. I wonder what Grant has in the
book?
I recently purchased a copy from the ARRL and it's well worth the $20
price. Table of Contents:
- Short Antenna Behavior
- A Better Way to Define Antenna Bandwidth
- Why Top-loading Can Improve Short Antenna Performance
- Top Hat Arrangements
- Inverted Cone Antennas
- Closed Antennas
- Antennas with Two Driven Elements
- T-shaped Antennas
- Inverted L-shaped Antennas
- Antennas with Four Driven Elements
- Spiral Antennas
- Small Horizontal Antennas
- Quadrature Feed Arrangements
Paul, W9AC
----- Original Message ----- From: "Tom W8JI" <w8ji@w8ji.com>
To: <Topband@contesting.com>
Sent: Thursday, August 30, 2012 7:02 PM
Subject: Topband: Small antenna book
While looking for something entirely different, I came across this. I
wonder if anyone has this book?
Grant, KM5KG, is one of the most experienced broadcast engineers
around.
http://www.km5kg.com/160meter.**htm
<http://www.km5kg.com/160meter.htm>
Grant claims:
"A New Book from Grant Bingeman, KM5KG
112 pages 8.5 by 11 inches
This book presents 30 practical wire antenna designs that fit inside
a 40
by 40 by 30 foot tall space, including the ground system. This
report is
specially written for the ham radio operator who lives on a typical
quarter
acre lot and has to maintain a practical budget.
E field radiation efficiencies of 75 percent are possible over a very
limited ground system of 18 buried radial wires only 20 feet long."
On the surface this seems to agree with what I find. There are dozens
of
ways to have about the same results. I wonder what Grant has in the
book?
73 Tom
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