3 Band HB9ABX Antenna
9th. November  2005

The new HF Antenna as 3Band Version

All my previous versions were monoband versions,
that means, one has to change the radiator to
change the band.
Now, I could make a 3 band version for the bands
14, 18, and 21 Mhz.

The length of the radiator is 145 cm with a
thickness of 5 cm (2 inch).
The HF properties are equally good as for the
monoband radiator.
The fieldstrength was measured at a distance
of 40 m at an elevation angle of 10 degr. and
the difference between the two antennas was
below 0.1 dB. (Comparing monoband 20 m
against 3 band version on 20 m).
Bandchange is done manually in seconds
without exchanging any part of the antenna.
The SWR is again 1.0 in the center of each
The MFJ-269 reads: R=50, X=0, SWR=1.0
measured after 2.5 m coax cable, antenna installed
on Honda Accord.
The SWR remains below 1.5 at the band ends.

The first QSOs today were on 17 m with Canada,
report received S7, and on 20 m with Finland,
received S9+10 dB.

In the next step I will try to make bandchange
with remote control.

Felix  HB9ABX