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THE ZZ "WAVE NET" ANTENNA BY
A DUAL LOOP - 80 AND 40 METER
HF WIRE ANTENNA PROJECTWhen you can't go out, you've gotta go
Sept, 2006 with new information
you want a full wave loop for 80 and 40 meters but have only a city
Got a 64 foot tower or equivilant support with enough space at the
top to add some insulators and a little time plus some wire? Got
some 16 foot supports for each end? Want a great signal on both
Then try this antenna project submitted by Mike Wigle, VE6VIS
and prepare for loads of
This antenna is the result of many hours of thinking and
tweeking and trial and error and starting again and again. It was worth
all the effort as I have come up with a very fine antenna that should make
the lives of many hams much better by using a loop antenna instead of the
inverted V's that so many of us use now.
antenna is basically a full wave 80 meter loop on top and a 40 meter loop
on the bottom all supported from a 64 foot center support, namely my
tower. They are both fed from the
center feed point with one length of 50 ohm coax. No tuner is required.
Use the standard formula: 1005/freqmhz, (your center frequency), for total
length of each "loop". Adjust for best swr by raising or lowering feed
point from top of antenna. It requires the 64 foot center support (tower
or mast) and 2, 16 foot end supports.
way of looking at this project is that two Delta loops, one for each band
and squashed to fit the space on the tower and your lot are paralleled and
fed with one length of coax.
The ZZ Wave Net is a revolutionary
new design in HF
The ZZ Wave Net starts with
the same principal as a
antenna bent into an inverted
Next, the ZZ is a folded dipole bent
into an inverted V
Next we pull
the ends of the folded dipole and separate
the middle as in the drawing
This allows us to install the antenna in a city lot and
keep the overall performance of a full wave loop
Then we add the 40 meter ZZ loop under the 80 and we have the
ZZ Wave Net, a dual 40 & 80 meter full wave loop
Below is how it looks installed on a 64 foot tower
with 16 foot
end supports on your city
(80 meter on
top, 40 meter on bottom)
80 meter apex to
end 70 feet
end to feedpoint 65 feet
40 meter feedpoint to end 36
40 meter end to bottom 34
Apex to feedpoint 24
Feedpoint to bottom 12 feet
Feedpoint is 4:1
Both loops feed from this point
End support to end
Measure wire and lay out at
base of tower.
Attach 1 litre bottle half full of water to the bottom
wire about 12 feet from the ends on both sides of antenna.This is so the
wires don't twist and so the antenna will have greater tuning
Attach apex of antenna to top of tower on a standoff and
preferably with a rope and pulley system.
Pull feedpoint up to 24 feet
Pull ends out to look like the
The wire length is the first thing
to get right.
Use the usual method of (low longer) ie: if the swr is
higher on the low freq then make the antenna longer and if the swr is
higher on the high side then make the antenna shorter.
Then the next
step is the distance between the wires.
The distance between the feed
point and the apex is 24 feet @ 80 meters.
The final tuning is done by
tightening the wires from the
So you get
the antenna pulled out to look like the
picture above, then you
can adjust the swr by tightening and
loosening the wires. You will see
a great range of
tuning here which is why this antenna design is
easy to tune.
The best way to do this is to mark the place
rope meets the tie off point. ( this is the trick
tuning this antenna) So, if for instance you have the
off to a tree. You mark the point where the
rope meets the tree by
tying a piece of string onto the rope.
This is your
Check the swr. Then loosen the rope so the marker
about a foot from the tree, Then check the match again. You
notice that it has changed. Now you can tune to a
point where the match
Shorten and lengthen the wire to provide the lowest swr
within the range that you can loosen and tighten the wires
for lowest swr and you will find that this antenna will
right down flat at the operating freq of your choice :)
Also you may
find that the antenna wants to be shorter
than the normal
calculation.This depends on a number of factors
like reflections and
hieght above ground.
Tune the 80 meter length first and then the
This antenna also works as an 80 and 20 or 80 stand alone,
stand alone, 40 and 20 etc.
Have fun :) Mike Wigle,
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