ANTENTOP- 01- 2018 # 022

Broadband 50- MHz Antenna

Broadband 50- MHz Antenna

Igor Grigorov, VA3ZNW

I just want a little privacy- sad Shrek (or something similar to that thing to avoid me a copyright problem). So I am. I decided to install plastic net for clementine flowers at my desk on the backyard. The clementine flowers are perfect do masking me when preparing BBQ, reading a book or just do experiments with antennas and home- brew radios. However it seems to me no sense to install just a net for clementine flowers without putting an antenna to this one. The net with flowers should perfect masking an antenna on it. The sizes of the net allow install there just antenna for 10 or 6 meter Band. I have chosen an antenna for 6 meters.

So the band for new antenna was defined. But design of the antenna was still unclear. MMANA helped me. With this free software I simulated an antenna that fit my flower net in dimension and satisfied me for electrical parameters. Figure 1 shows design of the antenna. Figure 2 shows Z of the antenna at 3 meters height above the real ground, the height what the antenna was installed.

Figure 3 shows SWR of the antenna at 3 meters height above the real ground. Figure 4 shows DD of the antenna at 3 meters height above the real ground. The antenna has rather broad pass band so I called it a Broadband 50 MHz antenna.

When schematic of the antenna was created, net for flowers was bought, there were arisen some questions about stuff for building of the antenna. I have a roll of black insulated stranded 18- AWG wire that was used for electrical purposes. This wire would be going for forming antenna.

Another question was- what should I use for the central insulator. I have a big junk box with some stuff related to radio and electronics. I try to keep lots things with that surplus because newer knows what you need in the future for your home- brew project. Inside of the box I found a caplug from forgotten connector. The cuplug was ideal form for central insulator. Bleeding resistor and antenna wires with coaxial cable was placed inside of the cuplug then this one was filled with an epoxy.

MMANA file may be downloaded at: http://www.antentop.org/022/50_MHz_022.htm

Figure 1 Schematic of the Broadband 50 MHz antenna

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