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Ohio SEC Hoping to Expand “NVIS Antenna Day” Activity this Year

04/06/2016

ARRL Ohio Section Emergency Coordinator Stan Broadway, N8BHL, says he has expanded participation in his section’s “NVIS Antenna Day” on Saturday, April 23, by inviting stations in neighboring states to participate. This year’s activity also will introduce the “anchor stations” concept, to provide more consistent signal reports. The Near-Vertical Incidence Skywave or NVIS antenna has gained traction among emergency communication groups and others desiring a close-in radiation pattern for regional work on HF.

“Working with antennas has been an integral part of Amateur Radio since the first hams took to the airwaves,” Broadway said. “Having the ‘right’ antenna becomes even more important when we’re acting in the interest of public safety. The Amateur Radio Emergency Service (ARES) organization in Ohio will put these two concepts together in another NVIS Antenna Day.” Getting under way at 1500 UTC on April 23, teams will begin making contacts to compare their antennas. Stations do not need to operate from the field but the location should allow room for several antennas.

“We don’t have an ending time, because some stations had so much fun — and so many pileups — last year that that they went on for quite a while past dark,” Broadway recounted.

Broadways said several stations in surrounding states have indicated they plan to be active in this year’s NVIS Day. “We’ve also received word a group in Texas will be doing their own NVIS exercise along with ours,” he added. “So, it looks like 40 meters will be busy with test signals!”

Broadway explained the “anchor station” concept this way: Team A puts together a low-altitude G5RV, then contacts Anchor A in Toledo, Anchor B in Dayton, and the Ohio Emergency Operations Center (EOC) station — know as “The Sarge” — for signal reports. “They then either adjust their design, or try antenna number 2, contacting the same anchors,” he said. “From their signal reports, they can determine right away which antenna is better and by how much.”

Anchor stations’ frequencies will be published, but participating stations may contact as many other stations as they can find, allowing each station to plot its coverage “footprint” to get a good idea of its capability for use in a real emergency.

Broadway said NVIS Antenna Day is not a contest but an activity focused on having teams or individuals research and determine the NVIS antenna designs they believe will work the best — then build and test them on the air. After the event all teams will file reports describing their antenna design and indicating how they fared.

“Each station then can rank its top three antenna performers with comments and ideas,” Broadway said. “Pictures are very much encouraged.” The sponsoring Marion County ARES team will compile the documentation, and narrow down the best-performing NVIS antennas across the region.

“The differences [among competing NVIS antennas] last year weren’t as dramatic as one might expect,” Broadway said. “Those fashioned after the military AS-2259 cross-dipole configuration appeared to be the best, but other designs worked nearly as well,” he pointed out. “We do understand that ‘regular’ antennas work well also — a lot has to do with band conditions.”



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