BD7PCO In response to user feedback, it's important to clarify that it's not a "balun" in the strict sense, because it doesn't perform a balanced-to-unbalanced conversion. The ends of both the feedline are unbalanced, so it should be called a "Balun-Unun" or a matching transformer. This design was based on this specific plan, with the matching device and cable integrated as a single unit. I really like this design. https://makerworld.com.cn/zh/models/2443158-10m-40m-efhw-juan-zhou-tian-xian?from=search#profileId-2785049 To be clear, Fair-Rite's magnetic rings are definitely better than those purchased on Taobao. The 20MHz back-to-back test showed a loss of only 1.59dB, which translates to approximately 83.27% efficiency (0.795dB). Please see the image directly below.
BD7PCO ft8wan I'll check it in the evening to see if it fits. The author also released a smaller, more compact version with a smaller handle and foldable design.
BD7PCO ft8wan Pendulum + oscillator, without wind rope, 641 grams.The wire is made of 0.75mm Teflon-coated wire.[upl-image-preview uuid=bfde6503-54be-4c4a-9905-642186a1005a url=https://storage.hamcq.cn/2026-07-07/1783434170-73040-tmp_8617c4123fe35567394127033497b06a.jpg alt=Image]
BD7PCO ft8wan 641 grams of a mass-spring system and a wire axis.20m of Teflon[upl-image-preview uuid=bfde6503-54be-4c4a-9905-642186a1005a url=https://storage.hamcq.cn/2026-07-07/1783434170-73040-tmp_8617c4123fe35567394127033497b06a.jpg alt=Image]
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