ANTENTOP- 01- 2013 # 017

Vertical Antenna for the 20-, 15-, 10- meter Bands (Antenna UW4HW)

Figure 1 Conical Antenna

Figure 2 Exponential Antenna

Antenna is fed by a 75- Ohm coaxial cable. Central core of the cable is turned on to the antenna wires. Braid of the coaxial cable is turned on to the antenna's ground. It is possible to use a metal roof as antenna ground. Six wires in length equal to the length of the antenna side may be used as antenna ground. The wires are placed perpendicularly to the antenna mast.

Copper wire in diameter of 1.5-mm (AWG 15) was used to make the antenna and the ground. SWR of the antenna was from 1.2:1.0 to 1.9:1.0 at the working bands. It is possible to make the antenna for other frequencies bands. Length of the antenna wires (from the bottom to top) may be found at the below shown Formula (it is for Alfa = 60- 70- degree).

The antenna worked very well in the practical operation in the Air.

Figure 3 Exponential Antenna for the 20-, 15-, and 10- meter Bands

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