|
Spring 2004 Issue |
|
A Portable EME Yagi
for 6 Meters |
|
When Gerald Williamson, K5GW, the owner of Texas Towers, and I got together a month before the 2003 ARRL EME contest to discuss what we might do this time around, more bands were bought up. With Al Ward, W5LUA, in the range circle and well equipped for the microwave bands, we all examined what bands were missing; 50 and 222 MHz were the only two remaining. I had already built a portable 222-MHz EME array, but 6 meters—now that was a challenge!
Work began on the only possible array, a
single Yagi. Most 50-ft. designs had posted gains of 14 to 15 dBi; we
wanted to do better, which meant longer. We took a look at different
2-meter designs that would yield +16 dBi, and after analysis, a 2SA13 file
looked promising. Redesigning the antenna for 6 meters, rounding to the
nearest 1/2 inch, and repositioning elements for a good match close to 50
ohms yielded a working model with ARRL Antenna CAD. A folded dipole was to
be used for the driven element due to the step impedance from 200 to 50
ohms. The antenna needed to be portable, no long-ridged booms, so
insulating guy cable was used. It is more than 200 miles from Tulsa,
Oklahoma to Allen, Texas, and time only allowed an 8-hour set-up time. Click here to return to this month's highlights Click here to subscribe to VHF and read more about A Portable EME Yagi for 6 Meters
_________________ © Copyright 2004, CQ Communications, Inc. All rights reserved. This material may not be reproduced or republished, including posting to a website, in part or in whole, by any means, without the express written permission of the publisher, CQ Communications, Inc. Hyperlinks to this page are permitted.
|