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Antentop is FREE e-magazine devoted to Antennas and Amateur Radio an
Special page devoted to
Cotenst for Antentop 01 2020
Custom Search
ANTENTOP- 01- 2020, # 024
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Table of Contents
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Table of Contents
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Page
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Cover
and Contents
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1- 4
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Antenna
Theory
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1 |
HF Helical Antennas:
Theory and Practice: Shortened HF Helical antennas have been used by radio amateurs in activity
on the Air during a long time. For example, shortened vertical
helical antennas have been used in hand held CB radio stations
(it is 11- meter HF band) from the 50- years of the 20- century.
Some manufacturers produce shortened helical antennas for military
and amateurs for lower HF bands- from 3 to 20- MHz.
As well shortened helical antennas are widely used in VHF/UHF
radio, as amateurs, as commercial...
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5- 37 |
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HF- Antenna Practice
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2 |
I built a Slinky antenna using four of the children's
toys. The aim is to have a helically loaded dipole which you tune
to resonance by shorting out turns at the end of the coils. Depending
upon the quality of the Slinkys you buy this isn't really an outdoor
antenna since corrosion can set in quite quickly...
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38- 39 |
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3 |
Outdoor Window Mounted
HF Helical Antennas: In the far 90s it
was installed and tested several outdoor HF helical antennas.
About two designs of the antennas is the article. The antennas
were mounted on the clothes drier installed at the first floor
of the 9 story building. Height from the ground to the clothes
drier was near two meter....
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40- 43 |
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4 |
The
Helical Whip for RV and Mobile Use: When I retired I found I needed
to reduce the complexity of my antennas for several bands, and
simplify their mounting and connections. I needed to cut down
on the time I spent setting up and disassembling antennas for
recreational vehicle (RV) and motor home use...
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44- 49 |
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5 |
Simple
Balcony Antenna for 10- 40 meter Bands:
I made one more experimental balcony antenna. The antenna
was made on the fishing pole in 5 meter length...
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50 |
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6 |
Low Height Antenna for the
160- meter Band: I made the antenna for operation at the field. The antenna
is very easy to build and shows high efficiency. My friends were
amusing when they have known what kind of antenna I used to...
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51 |
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7 |
RZ9CJ
Vertical Delta Antenna Compendium: I tested lots antennas on the Air. The simplest
and most efficiencies ones are vertical delta antennas. Below
there are figures of the antennas that were tested by me...
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52-54 |
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8 |
Just OCF Antenna Compendium from
different sources. May be useful to those who would like make
a simple wire antenna for several bands...
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55 |
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9 |
Antenna
with Rotating Directional Pattern for the 80, 40, 20, 14 and 10
meter Band: Valeriy Chihuga RA6AA and Georgiy Matcoyan UV6AF The antenna, developed by RA6AA and UV6AF, allows rotate the directional
pattern by changing the setting in the Antenna Tuning Unit that
may be sitting directly on the table at radio shack. The antenna
was made and tested at the end of the 80s in the USSR. Many of
the Soviet hams did the antenna...
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56- 60 |
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10 |
UR0GT
Wideband Antenna for 27- 30- MHz: It is simple vertical antenna that has low SWR at the
27- 30- MHz. The antenna has 50- Ohm
input impedance. Center frequency with low SWR may be adjusted
with help of variable capacitor in 20- 30- pF...
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61- 64 |
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11 |
Simple
Dipole Antenna for the 7 and 21- MHz Band: A dipole antenna
is most simple antenna ever. Easy to make easy to tune to the
working band. And it is benefit if the simple antenna works on
two bands. Below described simple dipole antenna that can work
on 7 and 21- MHz....
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65- 67 |
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6-
meter Antenna Practice
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12 |
End Fed 6- meter
Zepp Antenna with Resonance at 2- meter
Band: The September 2020 ARRL VHF Contest was coming and for this party I decided
to make an antenna for the 6 meters band. Of course, it is not
wise for me to install only single-band antenna for the 6- meter
band, therefore, using the my lovely simulating antenna program
MMANA I did simulation for antenna that could operate at 6 and
20 meters, and even at 15 meters with a slightly high SWR...
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68- 71 |
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VHF- UHF Antenna Practice
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13 |
RW4HFN
Vertical Clip Antenna for 145 and 435- MHz : It is very simple
antenna that has shape of a vertical paper clip can work at 145
and 430- MHz...
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72- 74 |
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14 |
RW4HFN
Clip Antenna for 145 and 435- MHz : It is very simple antenna that
has shape of a paper clip can work at 145 and 430- MHz...
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75- 77 |
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15 |
RW4HFN
Simple 145/430- MHz Antenna:
Igor
Vakhreev, RW4HFN
The antenna
made from aluminum wire in 6- mm diameter. Antenna has enough
wide passband so it is not critical to the sizes. Antenna may
be placed in vertical or in horizontal position...
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78- 80 |
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AVIA
Antenna Practice
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16 |
UR0GT
Broadband Avia Antenna Modified by RW4HFN :
I have made
the UR0GT Broadband Avia Antenna
. The antenna works good like it was stated. However, I
have decided a little modified the antenna to meet my requirements...
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81- 85 |
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Antenna
Tuning Unit
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17 |
Antenna
Tuner for Symmetrical Two Wire Line: Very
interesting practical design of the Antenna Tuner for Symmetrical
Two Wire Line it was published in the Forum at CQHAM.RU...
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86 |
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Artificial Ground
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18 |
Building a Ground Tuner (Artificial Earth) by
ZS1JHG: The conductivity of your ground varies from one location to the next.
This is of particular note to the mobile or portable radio station.
Using short vertical or end fed antennas a good low resistance
ground is required for efficient operation...
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87- 90 |
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Home Made Ham Equipment
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19 |
RF Generator for HF Bands 1.8- 30- MHz: For antenna measurements I used to a home brew RF- Bridge. It was very
compact device that can be used in the roof and field. However,
to test the antennas the RF- Bridge needs RF generator that provides
at least 50- mW of RF power. For my field applications it should be compact,
battery powered and stable source of RF energy ...
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91- 93 |
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20 |
Simple RF- Bridge: Design
and Applications: Lots measurements in antenna practice may be made with simple enough
home- made test equipment. One of piece of the equipment is an
RF- Bridge...
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94- 95 |
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21 |
Ferrite Clips and RF Current Sniffer Practice shows that even in case of a well matched with coaxial cable
antenna there is some RF current flowing on the outer braid of
the coaxial cable. It is so called common mode RF current. Causes
of the current are very different...
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96- 98 |
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History
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22 |
It is just a memory, for my QSO's that I made
in the far 1991 to 2004 years. I have tried to send QSL cards
for all of my QSOs. However, I do not know if my cards have reached
the correspondents. It was not a simple era in the ham radio in
the Russia...
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99 |
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BOOK
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23 |
Introduction
to Wave Propagation, Transmission Lines, and Antennas
My opinion
is that the best books for radio amateur are the Military Books.
The book gives clear information that could understand everyone.
No any formulas just practice that needs to know...
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100 |
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February 16, 2021 8:26
