C
Charger383
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Antenna Building
A 72 ohm vertical dipole antenna
Step 1:
Take 2,953 and divide it by the frequency in Megahertz that you want to
listen to (eg. 2953/144Mhz = 20.5 inches). This is 1/4th of a wavelength
in inches. Now cut sections of thin copper wire to this length.
Step 2:
Take 8,859 and divide it by the frequency in Megahertz that you want to
listen to (eg. 8,859/144Mhz = 61.5 inches) This is 1/2 of a wavelength
inside of 72 ohm RG-59 TV coax. Obtain a lenth of this stuff and cut it to
an odd multiple of the number of inches you got in step 2 (eg. 1 x 61.5;
3 x 61.5; 5x61.5; 7 x 61.5 et cetera, et cetera, depending on how long you
need.
Step 3:
I know "solder" is exclusively a noun and NOT A VERB to many people, but
this step requires you to SOLDER SOMETHING! strip the end of the coax and
solder one of the wires from step 1 to the center conductor and the other
wire from step 1 to the outside shield. MAKE SURE THEY DO NOT TOUCH.
NOTE:
Use really thin copper magnet wire and bare the enamel before soldering.
Step 4:
Tape your antenna to any non-conductive surface like your wall, your
bathtub, your window, your dead tree in the back yard, your china cabinet,
I don't care BUT DO IT THE FOLOWING WAY:
take the wire you soldered to the center conductor and tape up [by
up, I mean in the vertical direction facing the sky, the place where
airplanes fly, the clouds, heaven or the home of the holy deity of your
choice.]
take the wire you soldered to the outside shield and tape it down
[down is the opposite direction of up. It is where the dirt, sand,
soil, gravity and stuff comes from.]
Step 5: The final step.
Go to Radio Shaft and buy the connector to fit your scanner. Do you see
where your antenna is taped up and down? Good. Now go to the other end and
connect your adapter, after all I don't want you to ruin all that hard
work. Gratulieren meinen Freund oder meine Fruendin! You have successfully
built a 72 ohm vertical dipole antenna. Now, you can plug in your scanner
and enjoy the 3 or 4 dB gain over using a rubber duck.
Written by: brown82@MARSHALL.EDU
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A 72 ohm vertical dipole antenna
Step 1:
Take 2,953 and divide it by the frequency in Megahertz that you want to
listen to (eg. 2953/144Mhz = 20.5 inches). This is 1/4th of a wavelength
in inches. Now cut sections of thin copper wire to this length.
Step 2:
Take 8,859 and divide it by the frequency in Megahertz that you want to
listen to (eg. 8,859/144Mhz = 61.5 inches) This is 1/2 of a wavelength
inside of 72 ohm RG-59 TV coax. Obtain a lenth of this stuff and cut it to
an odd multiple of the number of inches you got in step 2 (eg. 1 x 61.5;
3 x 61.5; 5x61.5; 7 x 61.5 et cetera, et cetera, depending on how long you
need.
Step 3:
I know "solder" is exclusively a noun and NOT A VERB to many people, but
this step requires you to SOLDER SOMETHING! strip the end of the coax and
solder one of the wires from step 1 to the center conductor and the other
wire from step 1 to the outside shield. MAKE SURE THEY DO NOT TOUCH.
NOTE:
Use really thin copper magnet wire and bare the enamel before soldering.
Step 4:
Tape your antenna to any non-conductive surface like your wall, your
bathtub, your window, your dead tree in the back yard, your china cabinet,
I don't care BUT DO IT THE FOLOWING WAY:
take the wire you soldered to the center conductor and tape up [by
up, I mean in the vertical direction facing the sky, the place where
airplanes fly, the clouds, heaven or the home of the holy deity of your
choice.]
take the wire you soldered to the outside shield and tape it down
[down is the opposite direction of up. It is where the dirt, sand,
soil, gravity and stuff comes from.]
Step 5: The final step.
Go to Radio Shaft and buy the connector to fit your scanner. Do you see
where your antenna is taped up and down? Good. Now go to the other end and
connect your adapter, after all I don't want you to ruin all that hard
work. Gratulieren meinen Freund oder meine Fruendin! You have successfully
built a 72 ohm vertical dipole antenna. Now, you can plug in your scanner
and enjoy the 3 or 4 dB gain over using a rubber duck.
Written by: brown82@MARSHALL.EDU