ANTENTOP- 01- 2018 # 022

UR0GT Directional DEWD Antenna for the 145- MHz Band

UR0GT Directional DEWD Antenna for the 145- MHz Band

By: Yuriy Skutelis, RN3DEK

Credit Line: Forum at cqham.ru

There is presented directional antenna for the 145- MHz Band with active vibrator made on the base of UR0GT DEWD Antenna. Antenna has good SWR at the band and excellent F/B ratio. Antenna does not require follow to strictly dimension of the elements. So the antenna may be done ever by a ham who has no large experience in the antenna building.

Antenna has 50- Ohm input impedance that allows feed the antenna directly by 50- Ohm coaxial cable. Figure 1 shows schematic of the antenna. Antenna reflector antenna made of tube/rod in diameter 5- mm. All others antenna elements of the antenna made of tube/rod in diameter 8- mm.

It is possible use copper or aluminum stuff. Antenna has dielectric traverse. Dimensions are given in millimeter.

The antenna has reflector with bent ends. It is done to improve F/B ratio. Anyway you may play with model of the antenna in MMANA and check what you could reach.

Figure 2 shows Z of the antenna. Figure 3 shows SWR of the antenna. Figure 4 shows DD of the antenna.

73! RN3DEK

MMANA File of the UR0GT Directional DEWD Antenna for the 145- MHz Band may be downloaded at:

http://www.antentop.org/022/RN3DEK _022.htm

Figure 1

UR0GT Directional DEWD Antenna for the 145- MHz Band

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