It is nine snap on ferrite clips that are snapped on
to the coaxial cable. Quantity of the ferrite clips depends on
whether the position of the coaxial cable is not interacted on
to tuning of the antenna. When the needed quantity of the ferrite
clips is found, install a balun. It is possible to find lots description “how
to make a balun” in the internet. My balun also is very simple.
It is four coils turned around a ferrite ring. It is possible
use almost any ferrite ring with suitable sizes and permeability
100- 2000. Picture 2 shows antenna analyzer MFJ- 259B connected to
the tuned into resonance antenna. Antenna input impedance is 53-
Ohm at 14.075- MHz.
Picture 1 Shortened Dipole Antenna
installed at my balcony
Picture 2 Antenna Analyzer MFJ-
259B Connected to the Tuned into Resonance Antenna
Design of the antenna is very simple. For the antenna
it was used wire in diameter 0.7-mm (22- AWG). It is possible
to use any suitable wire in diameter 0.5- 2.0- mm (25- 14- AWG).
Homebrew insulators (made from plexiglass) used at the antenna.
Lengthening inductor is wound around plastic tube in 38- mm (1-1/2’’)
diameter. For the inductor it was used electro- technical wire
in plastic insulation. Diameter of the copper core is 1.8-mm (13-
AWG). Overall diameter of the wire in plastic insulation is 3.8-
mm (7- AWG).