Then the cable is turned to loop. Far end
of the length is soldered to the first (left) side of the prepared
cable. (In Russia the method of the making the coupling loop sometimes
is named -method of the DF9IV-)
The coupling loop is fastened
to the upper part of the antennaís loop with help of a Scotch
and ties. Below there are several simple rules how
to install the coupling loop.
At first, find on the antenna loop a point that is equidistance from left and
right side of the C2. It is the point of symmetry of the antenna.
At second, find the point of symmetry
of the coupling loop. The coupling loop is mounted in the top
of the antenna loop. Point of symmetry of the coupling loop should
concur with the point of symmetry of the antenna. Picture 4 shows the coupling loop on
At third, to
fasten with help of the cable ties the coupling loop to the antenna
loop at the distance of 6-8- cm from the point of symmetry of
the antenna loop.
Antenna was tuned (when it was placed on mast) in height
5- meters (it is from the ground to the top of the mast). Horizontal
wires and matching box with capacitors was at 3.5- meters above
the ground. A 2- meter ladder was used by me for tuning the antenna.
Antenna works fine ever at the small height. F/B ratio was near
20-dB in this case. Antenna was tuned to 7080- kHz in mind that
the resonance frequency move up (to 7100- kHz) at the height 8-
meter. Antenna is simple to tune to the resonance. It may be tuned
with help C2 (56- pF at Figure 1) to maximum RF- voltage at the long horizontal wire
or with help receiver to maximum receiving signal.