Build A Simple VHF/UHF "Scanner"
It should cover receiving only from the AM
aircraft band up thru the most used UHF frequencies in use by the
average "police" type scanner radio you may have. If you live in a
large metropolitan area, it should work well way beyond the UHF action
This antenna is
designed to be "cheap". So it must be constructed in such a way to be
supported from the top of the vertical "element" of the antenna and also
from the ends of the 3 "radials" that go away from the coaxial cable at
it's junction. One good way to suspend the vertical section is
to make a small loop on the end of the vertical section and suspend
it from a small non-conductive rope, cord or heavy string from something above. Make the length of the cord, rope,
string, etc as long as needed to get the vertical section and the
radials portion at least 3 or 4 feet away from any large metal
surface like house siding, roofing material, etc.
DANGER! DO NOT HANG OR MOUNT IT NEAR POWER LINES!
The antenna must be in the vertical position, meaning that
the tip of the vertical portion away from the coaxial cable must be up
towards the sky.
1. Coaxial cable. Should be any usable cable such as TV type or 50 ohm coax. Coaxial cable comes in many different types, but as a general rule for receive only functions, the TV type coax will work fine and is easy to find. Some TV types have an inner foil and the shield, which makes working with it a bit more difficult. You can not solder to the foil, only the shield! You will need enough coaxial cable to hang the finished antenna OUTSIDE and above the roof if possible. It can be used inside with reduced performance by hanging it from the ceiling near a window.
2. Wire for the radials. Final length....About 20 inches each (3 pieces) #12 or #14 works well and is more stiff than smaller wire size. See hints below!
3. Wire for the vertical section. Actually, this wire will come from within the coaxial cable by removing the outer insulation and the shield...see constructions tips below.
4. Soldering gun or iron, solder and sealer for the coax radial junction. This keeps the rain out and is very important.
5. Assorted hand tools, sharp knife for trimming insulation from coaxial cable.
All of these parts and tools can be found at any hardware shop or electronic store. However, building this should be easier and cheaper than repairing a Ford F150, however it shouldn't cost you an arm or a leg for parts. Click here for cheap parts for your Ford and possibly parts for your VHF/UHF antenna.
Construction and tips for building and using it.
In the drawing above, you will see the black section representing the coaxial cable.
You will also see the vertical section (A) on top.
You also should see the 3 radials marked
(B) hanging down.
Now take a close look at where the black portion of the coaxial cable ends in the center of the drawing. This is the point where the 3 radials are physically and electrically attached to the shield of the coax that has been exposed.
They should be soldered to the shield being
careful not to destroy the insulation for the "center" conductor of
the coaxial cable. These 3 radials in NO WAY should be attached to the
center conductor (wire) that is inside the cable. If this happens, then
the antenna will become useless! See the drawing.
For more ideas on ways to help make a more sturdy scanner antenna, just take a look at how Amateur radio operators do it using PVC! The basic design is the same, just a different way of using ham radio ingenuity! Click Here!
If you don't have the skills or just don't
want to build a good scanner antenna, then check out Scanner Master for
all your Scanner antenna and radio needs below.