| The quagi antenna is A
great antenna and is easy to construct,
doesn't cost an arm and a leg, and has
more gain than an equivalent yagi. I
could ramble on about why the quagi is
best but I'll save it for another page. The
boom can be made of any non conductor
such as wood, pvc, fiberglass, etc. Note
that pvc will sag over time, some support
on the ends will help this. I usually
choose pvc because it is cheap and
readily available.
The quad elements use #12 wire
supported at the top and bottom by
plexiglass(or any non conductor). An so
239 or suitable connector is soldered to
the bottom of the driven element and coax
connected directly to it. The driven loop
is open at the bottom with the center of
the coax connected to one side and the
shield connected to the other. The
reflector is A closed loop.
The directors are welding rod or any
stiff wire of about 1/8 inch will do.
Cut the elements as close to the plans
as possible, any slight difference will
degrade performance. Do not expect A flat
swr accross the band, I usually get a
couple of Mhz below 2:1 at 2 meters. A
common mistake is to assume that A wide
bandwidth or low swr means that the
antenna will work great, actually it's
often the opposite. A low swr accross a
wide range can mean low efficiency. A
dummy load has a wide bandwidth but isn't
A good antenna.
This antenna can be mounted horizontal
or verticle.
| |
144.5 |
147 |
| Element lenghts |
|
|
| Reflector |
86-5/8 |
85 |
| Driven |
82 |
80 |
| Directors (total of 6) |
35-15/16 to 35 in 3/16
steps
|
|
| |
|
|
| Spaceing |
|
|
| R-DE |
21 |
20-1/2 |
| DE-DE1 |
15-3/4 |
15-3/8 |
| D!-D2 |
33 |
32-1/2 |
| D2-D3 |
17-1/2 |
17-1/8 |
| D3-D4 |
26.1 |
25-5/8 |
| D4-D5 |
26.1 |
25-5/8 |
| D5-D6 |
26.1 |
25-5/8 |
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|
