The measurement was made at distance 5 meter far the antenna. At antenna clips an ATU (see References 1)
was used with the antenna. ATU (between coax and transceiver)
is a must for the antenna.
After numbers tests I did another modification.
1. Each vertical contains 20.2 meters of insulated copper wire in 1.5-mm
(15- AWG) diameter.
2. The coils (see Figure 4)
were deleted and verticals were connected straight away to pre
ATU (see Figure 5).
A counterpoise (I used metal balcony hand-rail) was
used with the antenna.
After this modification noise level decreased,
SWR was not changed. ATU (between coax and transceiver) is a
must for the antenna. With the antenna I did some DX QSOs, for
example, with KH0DQ (10-MHz, 589 to me) and
5Z4LS (14-MHz, 599 to me).
Of course, it is only a surrogate antenna, but the antenna is
worked, and works not bad.