GP for 7 MHz. |
I used a loop
on 7 MHz and it worked fine except in northern and
southern direction. So I decided to put up a GP to
cover all directions. The radiator is attached to a
tree and at the top it has a fishing rod with a hook
to fix it to the tree. |
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GP for 14
and 18 MHz. |
Limited space
for antennas made me to make a GP for 14 and 18 MHz.
Switching bands is done by controlling 2 relays which
are housed in a plastic box placed at the bottom of
the radiator. There are 4 radials for each band. SWR
is perfect for both bands and for 18 MHz condenser C
will do the trick. |
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Reversible
deltaloop for 7 MHz. |
When being
active from Gotland Island (IOTA EU-020) I have a lot
of space to put up antennas. Pretty high trees are
perfect for support points. When YV0D (Aves Island)
should be active in july 2004 I constructed a 2 el
loop for 7 MHz and put it up in direction to the
Caribbean. By adjusting a condenser I could get
some gain and there were no problem working them with
S9 signals. |
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3 el wire
yagi for 21 MHz. |
I got a nice
pile-up when using 100 W and this antenna pointed to
Japan. It is extremly lightweight so erecting it at
the top of a 10 m al-mast mast is done by hand. |
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Bobtail
for 7 MHz. |
The Bobtail
fed at the bottom of the middle tail and the next
antenna the Double Extended Zepp behave in a very
same manner. The gain and the radiation pattern is
comparable but if I have to choose I pick the Double
Extended Zepp. |
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Double
Extended Zepp for 7 MHz. |
Normally the
whole antenna is horizontal but I bent down the ends
of the antenna to fit between the two trees and it
worked nicely. |
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Hexbeam
for 21 MHz. |
In a contact
with a KL7-station I first heard about the Hexbeam
antenna. He said it looks like an umbrella turned
downwards without cloth and can withstand strong winds. I got
curious about the antenna and constructed one for 21
MHz. It worked at the first try and was a very
lightweight beam antenna. |
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Moxon
antenna for 14 MHz. |
This antenna
is a very kind one and often works at the first try. I
have tried several types ( vertical and horizontal) on
different bands and all have worked nicely. |
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Reversible
Moxon
antenna for 7 MHz. |
This antenna
is also called FBA (Flip Beam Antenna) and direction
of the antenna can be changed using relays or a switch.
Signals increase/drop 3-4 S-units when changing
direction. |
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10, 14 and
18 MHz dipole antenna. |
This antenna
is working fine on all 3 bands with only two hanging
points, trees or masts. |
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Diamond
antenna for 14 MHz. |
If you have
limited space for antennas and want to work DX on 20
meters this one can be an option. it is only 6 meters
wide compared to a normal dipole which reaches 10
meters. It has a low impedance feeding. There are 2
alternatives for matching the antenna to 50 ohm coax.
Use 2 75 ohm coax cables in parallell or use a 50/22
ohm balun. This one helped me to work 5W0GC and 9X0T
in spite of bad propagation in October 2018. |
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Veebeam
antenna. |
This antenna
is working nicely on all bands using an antenna tuner
between the 600 ohm ladder and the transceiver. Some
gain is also obtained. |
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Vertical
Moxon antenna for 28 MHz. |
There are
some reasons why you should endfeed your vertical
Moxon antenna. You donīt need a hanging coaxcable from
your radiator. You get an antenna with less windbreak
and an antenna in good balance. You just need to
voltage-feed the radiator with a simple LC parallel
resonant circuit like you feed a Bob Tail antenna or a
Half Square antenna. |
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Vertical
Moxon antenna for 14 MHz. |
This vertical
Moxon is also endfeded. The parallel
resonant circuit in this antenna uses a piece of RG8
coaxcable as a condensor. Remember to keep the open
end of the RG8 secured from water (rain) because of
high voltage. On 25 june 2011 this one helped me with
FO/F6CTL in Marquesas island. |
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Halfsquare antenna for 10 MHz. |
Due to QRM
into my neigbours HI-FI speakers using the Bobtail
described above I replaced it with a Halfsquare
antenna placed 15 meters out of houses. Using a link
with capacitor in serie the SWR is perfect zero. It
works fine even to the south but best directions are
west/east. The horizontal part of the antenna is
hanging in south/north direction. |
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Linear loaded
antennas. |
When space is
limited one has to design and build shortened antenna.
One way to do this is to use the linear loaded
koncept. By using 450 ohms ladder lines as stubs the
construction is a piece of a cake. I have used a
griddip meter to adjust the lengths of the stubs to
obtain the demanded frequency. Below you can find
dimensions for antennas for 7, 14 and 28 MHz. All
antennas are 70 % of normal lengths. |
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Rotatable
loop for 14 MHz. |
This simple
antenna is working extremly well. Compared to a Double
Extended Zepp at same hight and same direction it has
more gain and less noise. So it is a very attractive
antenna for portable use on both receiving and
transmitting side. |
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Ultralight
yagi for 28 MHz. |
This yagi is
small and very light by using plastic tubes as a boom.
The insulated wires for the element is inside of the
fishing rods who in original are 3 m long each. Keeping the
wires inside the rods makes the element a little bit
shorter and prevent bad SWR when raining. The
performance is good but if you expect high winds you
should use an aluminium boom instead of the plastc one.
This antenna helped me to work ZS8Z on May 22 2013. |
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2 el yagi for 28 MHz. |
This yagi is
quite similar to the one above but only using radiator
and director. It uses a 50:22 ohm balun to match the
lower resistance at the feeding point. The balun
includes a capacitor with value of 100 pF. A bit of
RG58 can be used instead of a ceramic one. |
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Mini Horse (MH)-antenna. |
- kicks like
a grown-up horse |
- takes the
space of a pony |
- broad as a
highway |
Ever looked
for an antenna which has good gain, nice F/B, 50 ohms
matching, excellent bandwidth, small turning radius
and great mechanical stability? This antenna is for
you! If you need a nec-file to play with just send me
a mail. |
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Compact Moxon
antenna for 10 MHz. |
This antenna
only needs 2 trees or masts to be hanged up in the
air. It works nice with about 7 dB gain and 15 dB F/B hanging 12 meters above ground. More gain and better
F/B if you can put it higher. |
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A 40/30/20
meter vertical on a flagpole. |
If you are in
a hurry getting on the air or donīt want to disturb
your neighbours with ugly antennas this antenna can be
the solution. It is a vertical tribander fixed to the
flagpole with radials on the ground. Traps are made of
coax cable using VE6YP coax trap program. |
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A 17/15/12/10
meter vertical on a fishing rod. |
Vertical
antennas with only 2 elevated radials are simple but
also quite good antennas for DXing. Another advantage
is that it can be placed where there is no good ground
or at the edge of your lawn so you can cut your grass
without thinking of radials on ground. The traps also
shortens the antenna a bit. |
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A 40 meter
vertical with 2 elevated radials. |
As mentioned
above vertical
antennas with 2 elevated radials are simple and very
cheap antennas for DX-ing. This one works fine from
7.0 to 7.2 with SWR < 1.5. If you use bare wire you
should prelong the elements with 4%. On 15 september
2010 I worked ZS8M using this antenna. |
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Moxon for 28
MHz. |
This antenna
is very smal but works very fine. The 1 mm insulated
wire is inside the fishing rods. Excellent front to
back and gain is nice for such a small beam antenna.
This one helped me to catch K9W on Wake Island on 12
November 2013. |
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Slope Loop for 10 meters. |
This antenna
is in perfect balance focused to a mast by some
fishing rods. The antenna is a 2 el Delta Loop with
sloping elements. The gain of the antenna is like a 3
element yagi and the front to back ratio is about 8
dB. |
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2 el phased
vertical for 40 meters. |
Combining 2
verticals with 2 elevated radials each and 3 pieces of
coaxcables gives you a phased vertical. Gain is 2-3 dB
over a simple vertical and F/B is about 15 dB. |
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2 el Diamond
Loop for 10 meters. |
This antenna
might be the smallest 2 element antenna with a turning
radius less then 1.6 meters. It gives a gain of 4 dB
over a dipole and the F/B is about 15 dB. It needs a
balun transformer 2.25:1 to match the 20 ohm impedans
at the loading point. |
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2 el yagi for
21, 24 and 28 MHz. |
Solarcycle 24
is here and the higher bands will hopefully be in good
shape. This antenna is small and perfect for portable
use. Elements are made of 1 mm insulated wires
supported by fishing rods. Gain is about 4-5 dB and
F/B is about 8-12 dB. Best performance on 28 MHz. |
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Coax dipole for
28, 24 and 21 MHz. |
The feedpoint
of this antenna is in the midpoint of the dipole. The
shield of the coax is used as one leg of the dipole.
The coax leg has to be trapped by a coil and a
condenser in parallell. The coil is made by the same
coaxcable and the condenser is soldered to the shield
of the coax. The condenser is a piece of RG58 coax cable.
Try it on your balcony. No radials needed. |
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Vertical
Diamond Antenna for
28 MHz. |
This antenna
gives a little more gain than a dipole at same height.
Using a 10 meter fishing rod as a mast it is very
light and is perfect for portable operations. |
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5/8 vertical
for 28.4 MHz. |
A simple but
effective antenna for DX-ing is the 5/8 wavelength
vertical antenna with only two radials. The trick is
to match the vertical to 50 ohm coax. By using a
tapped coil it is possible to get perfect match. With
this one at 1 meters height I worked XT2TT with low
power. At higher heigths the performance is greater. |
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21, 24 and
28 MHz dipole antenna. |
This antenna
is using fishing rod as the bearing frame for all
three bands. The wire for 21 MHz is inside the fishing
rod to prevent problems with SWR when raining. The
antenna works fine on all higher bands. |
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3.5 and 7 MHz dipole antenna. |
Using coax
traps and insulated wire this inverted dipole antenna
can be used on 3.5 and 7 MHz fed by one single 50 ohm
coaxcable. |
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ZIGZAG
antenna for 28 MHz. |
This antenna
is very small and should fit into any location. Boom
is only 0.7 meters and each element is less than 4
meters. I use a plastic boom so the antenna is also
very light. The radiation resistance is about 10 ohm
so a couple of quaterwave 50 ohms cables in parallell
is used to match 50 ohm to the radiator. It performs
as well as an fullsize 2 element yagi. |
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A 2 element
beam
antenna for 7 and 10 MHz. |
By using
coaxial traps you can build this antenna for 7 and 10
MHz. It is shaped as a Moxon antenna and works fine on
both bands. To mechanical balance the antenna a
support line is connected between the middle of the
reflector to the coax cable. |
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N-antenna for 7 and 14 MHz. |
This is an
easily built antenna for 2 bands. You need 2 fishing
rods mounted vertically, 21.06 m wire and an ugly balun. Best performance
is on 14 MHz. |
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One pole and
5 bands. |
This is an
5 band antenna using inv. vee-antennas for 7, 10, 14,
18
and 21 MHz (using 7 MHz wires). The wires are supported by a pole made of
fiberglass tube inserted into an aluminium pole. |
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MH mini yagi
for 18 MHz. |
This is a 2
element version of the MH antenna. As known the best
gain obtains from a 2 element yagi counted per
elements. Another element adds gain with 1-2 dB but
makes the antenna bigger and heavier. F/B affects in
small extent by more elements.
This
antenna is very small but the performance is like a
full designed 2 el yagi with a reflector. Matching
impedance is low but can be handled with a couple of quaterwave 50 ohms cables
in parallell. Using a ATU you can feed the antenna
directly with a 50 ohm coaxcable. As seen in the graph
the best gain obtains in the lower part of the band
and the best F/B in the higher portion of the band. |
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Vertical for
40, 30, 20, 17, 12 and 10 meter. |
This vertical
is doing a great job on several bands and fits into a
small garden. You can work on 40 to 10 meters using an
ATU. |
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Delta Loop
for 15 and 10 meter. |
The delta
Loop for 2 bands is used standing on the ground which
makes it easy to dismantle if the wind is to strong.
Data is almost comparable with dipoles for these
bands. |
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