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From Junk to the Super
Scanner Antenna on 10 Meters! Modify an 11 Meter Super Scanner Antenna for 10 Meter
Use By Ken, KD0AGV With special credit to Bill O'Connor, who
lives near Harrisburg Pa. Without his help, this project would
never have gotten this far!
 View of completed
antenna
Many years ago, the Super Scanner Antenna
M-119 by Antenna Specialists was a very popular antenna for 11 meter
use. It was designed as a "compromise" antenna with the properties
that made it into an antenna that was somewhere between a beam and a
ground plane type antenna. The "beam" property of the Super Scanner
was the result of electronically rotating the pattern rather than
using a rotor. The omni directional property and "beam"
effect was designed into the controls and phasing, enabling the
antenna to be used as a "beam" (sort of), or it could be
"switched" into the omni directional pattern.
This fit the needs of
many thousands of CB'ers who did not have the room for
both types of antennas! The resulting pattern of it was in 3 major
lobes spaced 120 degrees apart giving an almost circular pattern.
The switching of the lobes was accomplished by a control box near
the radio which sent signals to a relay box at the antenna which cut
in or out various relays and phasing lines to accomplish the pattern
change.
According to various sources,
the antenna had an "impressive" 5.75 dbi gain in the omni mode and
an 8.75 dbi gain in the directional mode. These "gain" numbers
really impressed a number of people who used them compared to
regular ground planes and the numbers especially
impressed those that could not have a beam for one reason or
another. Of course, those of you who know a bit about gain figures
see that the numbers are based on "I" isotrophic rather than "d" for
dipole which is the standard reference antenna! So to many CB'ers,
they saw some BIG numbers in those "gain"
figures. This project should be
only considered by experienced antenna builders who are familiar
with reading schematics, soldering, using electronic components,
work well with hand tools and have lots of mechanical ability in
order to fabricate the various brackets, mounting arms, coax
assemblies, etc. It is in no way meant to be a step by step
instruction guide but to give you the basics behind the construction
of the antenna. You will have to leave much to your "ham
ingenuity".
Here we will show you how
to duplicate the construction of the Super Scanner antenna modified
for 10 meter Amateur Radio use by using a Super Scanner antenna
calculator and a formula that we discovered by
experimentation!
A bit of background first. The original CB band
(23 channels), covered from 26.965mhz to 27.255mhz (290khz
wide), back when this antenna was very popular, so the Super
Scanner was designed for this band of frequencies and not 10
meters.
This project has attempted the design for use over the
entire 10 meter ham band which is 1.7mhz wide! It "favors"
the low end of the 10 meter band with lowest swr around
28.000mhz to 28.300mhz with a 1.3 - 1.4 to 1 swr over that
range. On
the high end at 29.100mhz to 29.700mhz swr was 1.8 - 1.9 to 1. Your
end results may be different depending on your design! In the Omni mode I got a flat 1.2:1. The single
vertical sections give a little higher SWR. Ive found it tunes
up quite easy.
The Scanner design program from
VE3SQB was used for the lengths and spacing of the various elements,
support arms, etc. Download and save it
here! You will need it!
A
workable formula below was derived by experimentation for the
phasing coax lengths from the relay box to the individual
elements due to the fact that there were no calculations in the
VE3SQB program for the phasing line lengths!
This formula appears to work
well: 220/freqmhz = length in feet
for each phasing line using RG-58 coax
Example: 220 / 28.500mhz =
7.71 feet = 92.63 inches. (round off to 92 1/2 inches) Editors note: We tried this formula for finding
the original phasing line lengths on an old Scanner antenna
used in this project using the low end (channel
1), frequency of the CB band and came up with the exact
length that was used on the CB band version. We have no idea why
Antenna Specialists used this length! But using the formula above
gives us the same length as the mfg used on the original
antenna....so it does work. You will
also need to refer to the original instruction manual. You can
download it at either of the links below. They are in pdf file
format.
http://www.cbtricks.com/ant_manuals/ant_spec_avanti/super-scanner.pdf
http://www.scribd.com/doc/3359466/superscanner
Unless specified, all drawings below were taken from
an original instruction manual for this antenna designed for 11
meter CB and are for reference only to give you some ideas as to
your construction.
 Drawing taken from
original Antenna Specialists manual The overall layout. Not to
scale!
In the drawing above, there
are three vertical dipoles each oriented 120 degrees around the
center section and insulated from and mounted on individual
boom supports. The supports are mounted to a triangular bracket that
is attached to the mast with "U" bolts seen in the drawing below.
 Triangular mounting bracket and rectangular
booms

The relay box shown
above containing relays, the phasing line connections and
switching connections, is mounted at the bottom of the
triangular mounting bracket.
Refer to the
pdf file instruction manual in the links above for the
schematics of the relay box and the control
box.
 Original Control Box 19-2425 (If
you are in luck, you may find an original relay box and
the control box complete on ebay or other classified ad
type sources)
 View of saddle bracket and feed points with center
conductor of phasing line connected to top half and shield to
bottom half. Note the insulator on the top half keeping it away
from the bracket!
 Side view of saddle bracket, insulator and support
arm
Additional notes and
information: The tips of the antenna were about
4' off the ground for the swr measurements.
The relay box on the antenna is the mfg part
number,19-1921. It only uses 2 relays, the measurements I took
for the coax was from the plate where the coax enters the relay box
to the end (at the 92.75 mark, I left about 1.25 inches to
strip back and connect). The coax is RG-58/U solid center. It
is easier to work with. The vertical sections are made up of
three pieces. I slid the bottom and the top piece into the
center section, drilled one hole and used new self tapping screws in
place of the old screws. Everything else is stock from the
original antenna.
The arms are 1 square aluminum
(it's carried at Lowes). The original length of the arms is
38.5. I removed 2 inches from the arms. Also you
need to be careful with the plastic isolators (top
sections). The end of the arms are re-enforced with steel
inserts (about 2 inches long, 1/16 steel). The aluminum
arms need to be strong enough to prevent twisting of the vertical
elements. I would either get the thickest walled aluminum you
can find or re-enforce the aluminum with some other metal. When
attaching the coax to the vertical sections, (SOLDER
SPADE LUGS) to the coax.
If the antenna is subject to
windy conditions, guy it below the cross arms using non-conductive
material strong enough to do the job.
Get help putting it in the air and stay well clear of
power lines!
Keep metal guy wires below the
lowest end of the antenna or break them up about every 7 feet with
insulators.
The phasing lines, connections on the relay
box, control box and the cross arms must be color coded in such a
way in order to know that the element directions match up with the
control box directional control! See the instruction
manual.
Further
Experimentation!
Initial experimentation with
the Super Scanner 10 meter modification was using vertical
polarization. Ken is in the process of further experimentation
using the antenna in the horizontal position with a rotor. The
unique mounting method simply "flips" it from vertical to horizontal
polarization. See pictures below:
 Supper Scanner mod in horizontal position
using unique 90 degree mounting. (Shown with rotor attached for
"aiming")
 Mounting method for horizontal polarization
using 90 degree bent into mast. (Rotor is out of picture below
the 90 degree bend)
Initial on the air results in the
"low" part of the Solar cycle and poor band conditions are very good
and the antenna is much less noise prone. 73, Ken
KD0AGV
Questions: For more information about this project, Email to Ken -
KD0AGV - fullofblarney at comcast dot
net
Editors
note: Our hat is off to Ken,
KD0AGV, for all his hard work (fun) in putting this project together
for all to enjoy. It's hams like himself that make this "hobby"
great.
Thanks Ken! 73, Don
N4UJW
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Notice! This article and project is intended
for educational an informational purposes ONLY for those
wishing to build or modify the antenna for non-commercial use.
The Antenna Specialists company is still in business and may
hold a copyright on this design! The name "Super Scanner" may
be trademarked by Antenna Specialists. No trademark or
copyright infringement is intended in this article and it
is intended for Amateur Radio Operator's personal use
only.
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