JA7NVF beam antennas

JA7NVF's Impressive Array of Antennas

Naomi Araya's antennas and shack near Misawa City, twenty-miles north of Towada, Aomori, Japan, where he lives

Towada is in Aomori Prefecture, the northernmost prefecture on Honshu. It is a relatively new city that was founded February 1, 1955. It merged with Towadako January 1, 2005, and now has an estimated population of 69,238. Japan's largest caldera lake, beautiful Lake Towada, is nearby.

Naomi Araya constructed this station near Misawa City, twenty-miles north of his home in Towada, to participate in a 2001 radio contest. It is located by Lake Ogawara, a half-mile from the pacific ocean, and in an area that is very flat with no obstructions throughout 360 degrees of azimuth. The beach nearby is famous as the 1931 take-off site for the first non-stop trans-Pacific flight to the USA by the Americans Clyde Pangborn and Hugh Herndon piloting the Miss Veedol airplane. The plane landed at East Wenatchee’s Fancher Field, Washington. Wenatchee and Misawa became sister cities in 1981 because of that common bond.

Naomi Araya's has upgraded his antennas nearly every year, but has had trouble beating other big contest stations that have better low-band antennas, so he constructed a two-element cubical quad for the 40-meter band and mounted it on a concrete pole. It is an interesting quad design that looks like a two-element stacked Yagi, because he didn't use spreaders. He used same element length for each element, feed each element through a 3/8 wavelength coax phasing cable, and used a remote switch to change the feed phasing so the elements selectively function as radiators or reflectors. The antenna can be physically rotated 120 degrees. That rotation, combined with the ability to switch either element to function as a radiator or reflector, makes it possible to cover 240 degrees of the 360 degree azimuth circle. (This design should have significantly better performance than typical two-element Yagis with coil traps.) Unfortunately, the antenna was damaged by high wind last year and isn't shown in the photo below. Noami is going to rebuild it with a little modification and will send a picture when he finished.

JA7NVF Antennas
Naomi Araya in his station
Naomi Araya in his "shack" 10-miles north of Misawa City. Naomi is 48 years old. He has worked as an Electrical Engineer for the U.S. Army Corps of Engineers at Misawa Air Force Base for 22 years.

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