by Jim, K4DLI and Dave, W7FB A presentation at the September 2009 NFARL Meeting. The presenters graciously made their presentation materials available for download. Click the links below to download the materials. Presentation slides (1.6mb PDF file) Power Transfer and Conjugate Match notes (PDF file) Power Transfer Worksheet (Excel spreadsheet) Thanks to Jim and Dave for a very informative presentation!
Continue readingAntennas
The 40M Extended Double Zepp
By Jim Streible, K4DLI SK There were many new and somewhat unfamiliar antennas used at this year’s NFARL Field Day. One of these was the one for the CW station. This antenna is basically two 5/8 wave antennas end to end. It can be fed with ladder line from the center insulator to tuner or it can use an impedance transforming length of ladder line to take the impedance to 50 ohms and fed from there to the rig with 50 ohm coax. That would limit it use (without a tuner) to a single band – 40 meters. To make […]
Continue readingThe Half-Square versus the Loop Skywire
by Jim Stafford, W4QO Appeared in QRP Quarterly, Fall, 2006 Up until about 8 years ago, I had an 80 foot tower with a TH-6DXX on it. It was quite fun working QRP with it on 20 thru 10 meters. Reports of “WOW, you can’t be QRP!” or “are you pulling my leg?” were quite common. But then an unfortunate incident involving a bulldozer and a hooked guy wire meant the tower was no more. Oh, it’s still out back awaiting the day when I can put it back up (if I ever do). I had been using a full […]
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