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All Wound Up About EFHW Transformer Winding
After successfully using an End Fed Half Wave (EFHW) antenna for SOTA, I decided to build a 10 to 80 meter EFHW antenna for my home...
Dan Koellen AI6XG
Feb 27, 20235 min read
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Evaluating efficiency, transformer and mismatch losses in toroid transformers - some observations.
Two methods for transformer loss are evaluated. We learn that mismatch loss must be accounted for.
Dan Koellen AI6XG
Jun 17, 20226 min read
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Toroid Transformers - How Hot Will It Get?
There are a number of factors in choosing a toroid for a RF transformer. While one may model electrical performance, calculate predicted...
Dan Koellen AI6XG
Mar 1, 202211 min read
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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
Oct 4, 20208 min read
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