ANTENTOP- 01- 2020 # 024

End Fed 6- meter Zepp Antenna with Resonance at 2- meter Band

End Fed 6- meter Zepp Antenna with Resonance at 2- meter Band

By: Igor Grigorov, VA3ZNW

The September 2020 ARRL VHF Contest was coming and for this party I decided to make an antenna for the 6 meters band. Of course, it is not wise for me to install only single-band antenna for the 6- meter band, therefore, using the my lovely simulating antenna program MMANA I did simulation for antenna that could operate at 6 and 20 meters, and even at 15 meters with a slightly high SWR. It was a dipole with two loading coils and additional wires for 15 meters.

I only need to go to Home Depot to buy tubes for loading coils and some hardware stuff for installation of the antenna. But before the trip a hurricane is happened... Storm wind and 200- mm rain with hails run through Niagara Falls. This hurricane destroyed my cucumber and tomatoes and pelted backyard with branches of the trees.

It is not so bad anyway the branches were prepared for fireplace for winter time. Then, two weeks later, one more almost the same hurricane (but not so much rain and no hails) run across the city. During the hurricane I went to backyard and realize that the new antenna will be in the center of the hurricane wind. Winter is going ahead with other strong wind and ice rain. So I decided install something simple and wind- resistant. Most simple antenna it is a Zeppelin antenna in form of one line. However it is one band antenna. So I decided install a Zeppelin antenna for the 6- meter band.

Figure 1 shows design of classical Zeppelin antenna for the 6- meter band. It is half wave antenna that matched with 50- Ohm coaxial cable through a quarter- wave length of two wire line. RF- choke is installed at the feeding terminals of the antenna. Most simple design of the RF- choke it is several ferrite rings on the coaxial cable.

Figure 1  Classical Zeppelin Antenna for the 6- meter Band

Before installation of the Zepp antenna in the backyard I decided to test the antenna inside my house. Below there is shown several steps for doing of the antenna. I start with RF- choke. RF choke for the antenna consist of seven ferrite tubes in 35-mm length and 17- mm OD. I do not know parameters of the ferrite tubes I bought it at a ham flea market several years ago. Photo 1 shows the tubes on the coaxial cable. Then the ferrite tubes were wrapped with electrical tape. Photo 2 shows the RF- choke.

The quarter- wave transformer was made from 450- Om ladder line that I bought at MFJ website. For antenna wire I have used a green wire (this wire used for GROUND in electrical connection). Copper core of the wire had 1.5- mm diameter and OD of the wire was 2.2- mm.

Photo 1 Ferrite Tubes on the Coaxial Cable

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