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Translation into the Dostoevsky language by Sergie Gorbunov, UA3TJC
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CENTER-FED MONOBAND INVERTED LONG WIRE VEE
Edited from a project by
M. Noll, W3FQJ
in the book "73 Dipole and Long Wire Antennas"
published by Editors and Engineers, Ltd, Copyright
Edward Noll had many great antenna projects in his
Lots of them were based on the 3/4 wave length per side
Presented here is one of them!
Antennas can be resonated to a specific frequency by
making their overall electrical VIEW
length a whole multiple of a
half wavelength. There is a rise in gain with each half-wavelength
addition. In the case of a horizontal antenna, the antenna becomes
more directive with antenna length.
The addition of leg lengths
in odd multiples of a half wave-length ensures a low impedance
center feed point because each leg of such an antenna is an odd
number of quarter waves-lengths long.
This project will
enable you to build a monoband long wire inverted vee
wave length sides that will have a bit of gain, (amount not stated
in the book), for high band operation and long distance compared to
a standard 1/2 wave dipole because of its lower vertical angles of
radiation, and added leg length. The longer the leg lengths in odd
multiples, the more the gain.
It amounts to a very low cost and
effective antenna. It is also less directional than the
horizontal dipole or straight long wire antenna.
On a horizontal
3/2 wavelength dipole, the antenna presents four major lobes
and 2 minor lobes.
The four major lobes are at:
45, 135, 225,
The two minor lobes are at:
90 and 270
with respect to the horizontal antenna as viewed from
above as in line below:
180 Degrees ______________________ 0
practical 20 meter basic design, assuming a 25 to 45 foot mast is
used can be determined by the formulas below:
(As always, it is
wise to cut lengths long and trim as needed for best
Leg length = 738
divided by frequency in mhz
each half = 738/14.2 = 52 feet
Line length =
divided by frequency in mhz
Line length = 650/14.2 = 45 feet 9
The "magic" numbers
650) in the formulas above appear to be arrived at
by trial and error by Ed Noll and were presented in a chart in the
To arrive at the "magic" numbers (constants) for each
formula for different leg lengths and feeder lengths as determined
by your particular lot size, just do the following:
longer leg lengths add 492 to each odd multiple of a 1/4 wave
3/4 length =
5/4 length =
7/4 length =
For longer feed line lengths,
(REMEMBER THAT FEED
LINE LENGTH MUST BE AN INTEGRAL MULTIPLE OF A HALF WAVE LENGTH
TAKING THE VELOCITY FACTOR OF THE LINE INTO
Example: 1/2 2/2 3/2 4/2
VF .66 LINE VF .81 LINE
Notice that that for .66vf line,
325 is added each time and for .81 line,
400 is added each time for the constants.
(There were no other constants for other velocity factors in the
articles in the book, however, you can still use the formula....Line
length in feet (1/2 wave) = 492 X VF / freqmhz for determining
the electrical half wavelength of a
Higher gain figures
can be accomplished by bending the legs forward toward the receiving
See the 3 Halfwave Vee
Beam based on these
same principles by Ed Nolls, W3FQJ.
If you can find a copy of Ed's "73 Dipole
and Long-Wire Antennas", by all means, get it.
Ed also wrote many
other books related to radio. Many are out of print but still
can be found.
You will have many hours of fun building and
experimenting with Ed's designs which are a culmination of his many
years of very talented dedication to Amateur
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