Amateur Radio Station VE9BGC and Antennas Design
In 1996 my father
mentioned he had a Realistic Navaho base CB he was not using. It sparked my
interest as I always was fascinated with radios. I still have the radio. It
was fun and I made a lot of good friends. Several months later amateur
radio also got my interest. I became licensed in 1997.
My main interest is antennas design. I also teach antennas and transmission lines to new students. My other great interest is DX expeditions from lighthouses.
I run a 100w Kenwood TS-850S operation on various wire antennas of my design. One is a combination 80m/20m (60 feet) with parasitic ground (17 feet) giving a gain of 10.7 dbi. I also have a 80/40/20/10 Alpha Delta dipole. My VHF/UHF radio is a Kenwood TM-V71A for my house and mobile.
Amateur Radio Station VE9BGC
The image below is of the 80/20m dipole (60 feet) with a parasitic ground. The parasitic ground which is 17 feet above the ground (1/2 wave below 20m dipole) gives 2 db more gain by reflecting the RF back up in phase. The spacing (8 inches) is critical as it brings both impedance to 50 ohms.
My other design is a portable 20/15 vertical yagi with 20m reflector. Yes, it is a yagi with a reflector on the left. The radials are just the bottom part of the yagi that is open to raise the impedance to 50 ohms. The lowest part of the radial is 5 feet above the ground. Having the whole antenna above the ground will give more gain and eliminate ground noise. The director has a second element tuned to the 15m band. The director has two radials tuned to 20m and two tuned to 15m. The reason for this design is to have the highest performance close to salt water and to be portable. The assembly takes about 2 hours and the tuning (SWR) is perfect at 1.0. The whole assembly comes apart and fits is my car.
Another design is a 17m Sterba Curtain 93 feet long. The top is 54 feet high (1 wavelength) and the bottom part is 27 feet (1/2 wavelength. The East lobe is aimed at England and West lobe is 8 degrees south towards Texas giving the best coverage to Europe and USA. The wires are #12 copperweld steel for strength.
Below is the matching serial tranmission line.
It is 23 feet of 450 ohm ladderline with 4 feet of RG-59.
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