01- 2012, # 016
Ground Plane for the 40,-30,-20 and 17- meter Bands
antenna is very simple. It is just vertical radiator in 10- meter
length that is matched at the each working band by its own matching
unit that is switched on with help of relay. However to the design
I came not straight away. There were tried several multiband antennas
(for example, antennas from References
1 and 2) but for some reason no one of them did not satisfied
me. I could not get good SWR at each of desirable working bands
of the antennas.
of mine, UA7A, ex UA6CW, advised to me to use the described below antenna.
He helped to me to calculate matching circuits for the antenna.
shows schematic of the antenna. Figure 2 shows schematic of the matching units
for 40,- 30,- 20 and 17- meter
Bands. To eliminate static from the antenna the vertical radiator
is grounded through pair resistors in 430- kOhm/2- Wtts.