ANTENTOP- 01- 2011 # 015

145- MHz J- Antenna with no- Mast RF Current

The publication is devoted to the memory of UR0GT.

By: Nikolay Kudryavchenko, UR0GT

It would be very conveniently if a J- Antenna would be grounded to the metal mast. However there is a problem with an RF- current leaking from the J- Antenna along the mast. It is a very simple method

The MMANA model of the 145- MHz J- Antenna with no- Mast RF Current may be loaded: http: // www.antentop.org/015/current_015.htm

to block the current. Just a lambda/4 resonator should be installed straight under the J- Antenna. The resonator may be installed at the opposite side to the antenna or straight away under the antenna or may be installed two resonators, one from the opposite side of the antenna another under the antenna. Program MMANA helps us to investigate all of these implementations.

Figure 1 shows the J-Antenna with opposite choke resonator. Figure 2 shows the current distribution in the system- J-Antenna with opposite choke resonator - Mast. Figure 3 shows impedance the antenna. Figure 4 shows SWR the antenna. Figure 5 shows DD the antenna.

Figure 2 Current distributions in the system- J-Antenna with opposite choke resonator - Mast

Figure 1 J-Antenna with opposite choke resonator

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