antenna is a variant of well- known T2FD antenna. This modified
antenna have been working at my ham station for decade years and
showed itself as low noise antenna that works from 1.8- MHz to
30- MHz, does not required ATU, easy to repeat, allows to receive
weak DX- stations (especially on low HF- Bands), does not receive
static interferences and has lots other advantages. Figure 1
shows design of the antenna.
made of a copper wire in diameter of 2.5- mm (10- AWG), insulating
spacers made of wood, stick has holes between antenna wires on
distance of 87- cm and the stick has 1x1 cm cross- section. Load
resistor should be non- inductive and bear at least 25 percent
of power going to the antenna. Two wire line has length in 11-
meters, made of a copper wire in diameter of 1- mm (18- AWG),
distance between wires is 7.5- cm.
used home- made plastic spacers in the two wire line. Antenna
was installed on a mast in 8- meters high. Matching transformer
contains 16 turns, the transformer was winding on a flayback
ferrite core from an old color CRT TV, four turns on each side
(almost similar transformer is described at: http://www.antentop.org/008/ua3znw008.htm). Transformed was
placed in a tin can, that was hermetically soldered.
was fed through a 75- Ohm coaxial cable. Antenna has SWR 1:1 to
1.4:1 at 1.8- MHz to 30- MHz.
noticed that antenna does not produce almost any interferences
with TV at working the antenna in transmitting mode.
73, de RK1AC