2.
The next step is to make inductor.
The inductor will be placed inside of the item 5. It
needs to save the inductor from atmospheric influence- rain, snow,
etc. At first prepare low cap (one of item 6). Install at centre
of the item 6 the RF- Socket (item 8). At the second cap (one
of item 6) make two holes in dia 2- 3-mm for wires going from
the inductor to the EH- Antenna. Note, that after antenna tuning,
the holes should be covered with glue from Glue Gun.
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Inductor is wound at the item 7. Divide wire (item
9) in two lengths by 4- meters each. Twist the wire, 2-3 twist
on centimeter. Then one end of the Wire is fastened to the form
(item 7) leaving 100- 150- mm of the wire free.
Coil 39 turns and second end of the wire is fastened
to the form. Beginning and ending parts of the inductor is coiled
with some gap. Do tap from 5.5- turn from the bottom. It is tuning
tap. Antenna is tuned by the tap (choosing the tap from the inductor)
or moving coils coiled with gap between each other. The inductor
is fastened with help of Glue- Gun at the bottom cap. Figure 3
shows inductor installed on the coupling cap.
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3.
Antenna tuning
Solder upper end of the inductor to one copper plate,
bottom end to another. (Inductor is still outside the coupling
box- item 5.) Tune the antenna. With help moving of the upper
coils the antenna is tuned to needed frequency, with help moving
the bottom coils the antenna is tuned to minimum SWR and maxima
EMF. After tuning of the inductor, glue the coils by several drops
of the glue. Tuned inductor should be placed inside item 5, then
item 6, then protect with the glue all jointing and holes of the
detail. Figure
4 shows the inductor inside of the coupling.
That is all. Flat EH- Antenna is ready. I installed
the antenna on a wooden mast in 2- meters length. Three guys supported
the mast. Antenna was fed by coaxial cable RG-58/U- MIL in length
19.2- meters. Antenna was installed near my home, in 12 meters
from the wall. Coaxial cable that is going from Flat EH- Antenna
was buried into the earth (on a small depth). Near the antenna
were trees that were higher that the antenna. Figure 5 shows the installations of the EH- Antenna.
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Figure
4 Inductor of the EH- Antenna inside of the Coupling
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