Dan Koellen AI6XG Jun 16 13 min Don't Fear the Smith Chart Like many radio amateurs I was initially intimidated by the Smith chart. Transmission line and antenna theory, unfamiliar terms and...
Dan Koellen AI6XG Oct 4, 2020 8 min Trapped 20/30/40 Meter EFHW Antenna An End Fed Half Wave (EFHW) antenna for operation on 20, 30 and 40 meters was built for SOTA operation. By using traps, the antenna...
Dan Koellen AI6XG Jun 29, 2020 7 min Big Font Clock Update: Dimmer-Interface PCB and Setup Instructions. A prior post described the development and build of a clock to display time and date for UTC and Local. The clock characters are large,...
Dan Koellen AI6XG Jun 6, 2020 4 min End Fed Half Wave Antennas: More About the Primary Capacitor I recently posted a blog claiming that a capacitor in the primary of the matching transformer is not needed for end fed half wave (EFHW)...
Dan Koellen AI6XG May 27, 2020 3 min End Fed Half Wave Antennas: Is a Primary Capacitor Really Needed? In my research on End Fed Half Wave (EFHW) antennas I found that nearly all have a capacitor in the primary (rig) side of the transformer....
Dan Koellen AI6XG Feb 9, 2020 9 min Big Font Clock - Relieve for Old Eyes Recently the Maker Space that I frequent received a number of 4 line 40 character (4 x 40) LCD displays. They asked me to figure out how...
