The publication is devoted to the memory of UR0GT.

Credit Line: Forum from:

www.cqham.ru

By: Nikolay Kudryavchenko, UR0GT

One Ground Plane allows get one directional switchable DD. For this purpose to the GP a two wires should be added. With help an RF Relay (or just with help of manually installed jumper) the wires turn on to Director and Reflector. Length of the GP should be taken a little more than lambda/4. For the minimum SWR the antenna tune up with the help of a capacitor C1.

Figure 1 shows the design of the antenna.

Figure 2 shows Z of the Bidirectional Vertical Antenna for the 20- meter Band.

Figure 3 shows SWR of the Bidirectional Vertical Antenna for the 20- meter Band.

Figure 4 shows DD of the Bidirectional Vertical Antenna for the 20- meter Band.

The MMANA model of the Bidirectional Vertical Antenna for the 20- meter Band may be loaded: http: //

www.antentop.org/019/ur0gt_directional_019.htm

73! de UR0GT

Figure 1 Design of the Bidirectional Vertical Antenna for the 20- meter Band

www.antentop.org

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