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6 METER EDZ SIGNAL
SQUIRTER (DESIGNED FOR 50.200mhz + -)
The Six Meter Extended Double Zepp is a very easy and
inexpensive antenna for the 6 meter buff to build in about an hour or less
and will add about 3 db to your signal from it's broadside bi-directional
pattern when installed about a half wave up from the ground. You mignt
call it a diplole with gain! All of the materials used to
build this antenna can be found locally or you may even have them laying
around.
The wire for the main two halves of the antenna can be any
strong wire size such as #14 stranded copper. The lead-in to the tuner can
be 300 ohm "twinlead", regular lamp cord split in half or 450 ohm ladder
line.
Keep the antenna and all of its parts including the line
going to the tuner as far away from metal objects as possible to prevent
pattern distortion, detuning, and swr problems. Support the antenna from
ropes or cord of the proper length to trees, buildings, etc from the end
insulators and as high as possible. Standard "egg" insulators or any
other type of insulator (non-conductive) can be used on the ends and in
the center.
NOTE: Cut the lengths for
the horizontal sections about one foot longer than the actual lengths
shown in the picture below so you will have enough wire to wrap thru the
insulators and then back on it'self and tied tightly.
Below is a
"crude" drawing of the antenna design....the pattern will be "looking at
you and away from you as with any standard
dipole.

You should end up with the
approximate lengths shown in the picture drawing
below.
Solder the connections at the center insulator and
seal well with electrical tape and some kind of sealer appropriate for
outdoor use. (you want to make the connections water tight if
possible)
Attach the ends of the downlead to the "balanced"
terminals of your tuner, fire up your 6 meter rig on 50.200mhz AM,
using just enough power to check swr per normal procedures and trim
antenna as needed for lowest swr as with any antenna
project. (You may get lucky and not have to do any trial and
error!) (Make sure you give your call and say testing while checking
the swr!)
HOW TO CALCULATE APPROXIMATE LENGTHS
FOR THE EDZ - OR HOW TO GET A MATH LESSON FOR FREE!
Since
this is an Extended Double Zepp design, each half of the antenna is 5/8
wavelength long. If you remember, a half wave diplole length is
calculated using the formula 468/freq in mhz = total length in feet. A
half wave when converted to decimals = .5 A full wave =
1.0 Therefore we can determine what 5/8's wave length long would be by
first converting the formula above to a full wave length, 468 x 2 =
936
SO, 936/our freq in mhz would give us
the total length of a full wave length antenna, but we are looking for
5/8's of one wave length for each side so we have to determine what 1/8 of
one wave length is and then multiply by 5.
Example: Divide 936
by 8 (number of 8ths in one wavelength) = 117 for 1/8 wave
length. We're looking for the 5/8's formula so: if 117 = 1/8 then
5 x 117 = 585 (our magic
number!)
So using this new found number substituted in the
formula we have: 585/50.2mhz = ll.65 feet per side! NOW WE KNOW EACH
LENGTH PER SIDE! BUT WAIT!!!! HOW MUCH IS .65 of one foot IN
INCHES?????
"MAN! I'M NEVER GONNA GET THIS
ANTENNA UP BECAUSE OF ALL THIS MATH!" Don't
be so impatient!!!!!!!
Here is how to find out how much .65
of one foot is!
Since we have decimals in use, .65 is the same as
saying 65%.
Simply multiply 12 inches X .65 = 7.8 inches!
Our length
for one half of the antenna is = 11 feet + 7.8 inches = 11 feet 7.8 inches
per side or rounded off.....11 feet 8 inches! More formulas and another EDZ project
here!
Oh! I
hate math! "But sometimes ya gotta" Good luck with your project!
73
This
project is based on an article published in
CQ VHF
MAGAZINE PUBLISHED SEPTEMBER 1997 RE EDITED AND CONDENSED FOR
CLARITY!
GET CQ VHF
HERE!

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