ANTENTOP- 01- 2018 # 022

UA6AGW Antenna with Vertical Radiators for the 20- meter Band

UA6AGW Antenna with Vertical Radiators for the 20- meter Band

Vitaly Gluhov, RA9MAI

Credit Line: CQ-QRP # 63, pp.: 18- 20

The antenna, made on the base of UA6AGW Antenna (see References), was designed and build in 2017, at first at all for fixed and field operation. Author is very appreciated to Andrey, IP50AA, for his very useful advices on the antenna design.

Design of the Antenna:

Figure 1 shows design of the antenna. It is a modification of UA6AGW antenna where horizontal radiators are placed in vertical plane. To increase efficiency of the antenna the main loop made of copper tube in diameter of 20- mm. Diameter of the main loop is 800- mm. Variable capacitor C2 in 3- 30-pF with air dielectric and gap between plates in 1.5- mm is switched to bridge of the loop. Inside of the loop is placed a length of a coaxial cable RK-75 in diameter of 10-mm.

(Note from I.G.: It is possible to use any coaxial cable with outer diameter of 10- mm).

The braid of the cable is connected to C1. Central core is not connected. The capacitor intended for initial tuning of the loop to the 20 meters. In author design it was used high voltage fixed capacitor in 10- pF. Vertical radiators of the antenna made of aluminum tube in diameter of 20- mm and length of 2 meter each. Capacitors were installed in waterproof plastic electrical box. Figure 2 shows the capacitors in the box. Figure 3 shows main loop with capacitors' box. Figure 4 shows installed UA6AGW Antenna with Vertical Radiators in tested position.

Figure 1 Design of the UA6AGW Antenna with Vertical Radiators

CQ-QRP # 63

http://qrp.ru/cqqrp-magazine/1411-cq-qrp-63

www.antentop.org

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