SWR at 7, 10 and 14 MHz was near 1:1,1. While
two weeks running the antenna on the bands I did a hundred CW
QSO with practically of all the European countries and some
district of Asia of the former USSR. I have received 569… 599.
The antenna works with low SWR at 80- meters, however only local
QSO was done. At 18 MHz the antenna has SWR 1:2. For testing
the antenna I used a home- brew transceiver made on the base
of old Russian receiver
R-250 and ATU MFJ- 945E.
of the UR5WCA Balcony Antenna for 7, 10 and 14- MHz
Figure 4 shows modification
of the antenna that increases it performance. Inductors L1 and
L2 were coiled by insulated copper wire in 1.5-mm (15- AWG)
diameter, spacing between turns is 2-mm. Form diameter is 35-
mm (was used PVC tape tubes), numbers of turns are 29,
tap from 9 turn from cold end. FSM (Field Strength Meter)
displayed increasing of electromagnetic field to 30% compare
to antenna without matching coils.