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Antenna info
Simple Wire Antennas
Please Read
First !
The installation and testing of antennas may be dangerous ! Before installing
any antenna make sure that there are NO overhead power lines, over hung tree limbs or any obstructions that could touch the
ends of the antenna. Lethal voltages and currents are present during test even with only 100 watts of power. Most
antennas perform best at least 1 wave length above the ground. 40 feet above ground is as low as
I would like to go . Antennas will work at any height but SWR and signal strength will suffer.
Antenna
Comparisons:
You will always here this G5RV work better then antenna X. Well my question to those
people is the only way to do a comparison is to do a A/B comparision. That is have both antennas up at the
same time and switch from one to the other and get signal strength readings. Also, check noise figures from one
to another. This should be done under more then one Prop conditions.
Test Equipment:
MFJ Antenna
Analyzer
Useful to profile antennas. Also acts as a TDR, Time domain Reflectometer.
AMQRP Antenna
Analyzer
One of the best and least expensive analyzers to use. It is in kit form and cost about $300.
Half Wave Dipole
This antenna is 1/2 wave length of the operating frequency, single band
NO TUNER required feedpoint impedance about 75 ohm
Single wire (OCF) Off Center Feed
Only one
wire in the air, multi-wave lengths of operating frequency, forward gain, Can be made into multi band antenna without
a TUNER. A single wire tap from one end at 1/4 wave length of the operating frequency. The single wire goes
into a isolation transformer. One side of the transformer has a ground wire and the single wire from the antenna, the
other side has a SO 239 coax connecter to connect the feedline to the radio. The ground wire is connected to a ground
rod driven in the ground at the transformer. This antenna is very long, more then 400 ft in length and should
be as high as possible.
OCF Dipole G5RV or Windom
Tuned Loop Antennas
Delta
Loop
Full Wave Loop
Half Wave Loop
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