ANTENTOP- 02- 2004, # 006

Multirange Trap Antennas

Figure 4 Antenna W3DZZ

meters, lengthening inductor for 80 meters, and shortening capacitor for 20, 15 and 10 meters. The antenna (Figure 4) does not work at WARC bands. However, the antenna does not work properly at 20, 15 and 10 meters. You can see data obtained with Free Antenna Simulation Program MMANA

(MININEC based) for the W3DZZ (see Figure 4). Antenna wire has diameter of 2 millimeters. You can see, that a SWR at 20, 15 and 10 meters is too high. It is impossible to find such length of the antenna and data for trap that the antenna works at all of the ranges! So, an ATU and a good coax is need for the antenna if you work at 20, 15 and 10 meters.

SWR at 80 meters W3DZZ Antenna

Current Distribution at 80 meters W3DZZ Antenna

http://www.antentop.org/

Page 51