Construction
plansA 1/4 wave
ground plane ham radio antenna for vhf can be
constructed easily from inexpensive parts.
All that is needed is an so 239
connector, a few feet of stiff copper wire, a u-bolt
and a small scrap piece of angle
alluminum or other suitable pice of scrap
metal.
Solder the vertical antenna radial to the
inside of the so 239 connector. Bend the
ends of the outer radials into a small
loop and connect them to the mounting
holes of the connector. Apply solder to
this joint with A high wattage iron or
torch.
Drill or cut an appropriate hole in
the angle for the so 239 to pass through
and fasten the 239 to the angle with the
retaing ring that. You may need to cut or
grind the screws to get A snug fit.
Drill holes into the angle for the u-bolt
and bend the rods down to about A 45
degree angle and thats it, your done.
It's A good idea to apply some sealent
around where the vertical radiator enters
the so 239 if the antenna will be used
out doors, coax seal will work fine for
this. It would also be best if you apply
A large blob of solder to the ends of the
wire, remember what your mother told you
"those things could put your eye out".
Below is A drawing with the
deminisions for three vhf bands. Of
course just as with any antenna, you can
come up with your own construction scheme.
Just so the antenna lenghts are correct.
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