{"id":36661,"date":"2019-03-22T08:15:10","date_gmt":"2019-03-22T12:15:10","guid":{"rendered":"https:\/\/swling.com\/blog\/?p=36661"},"modified":"2019-03-22T08:15:10","modified_gmt":"2019-03-22T12:15:10","slug":"building-a-20-meter-self-tuning-magnetic-loop-antenna","status":"publish","type":"post","link":"https:\/\/swling.com\/blog\/2019\/03\/building-a-20-meter-self-tuning-magnetic-loop-antenna\/","title":{"rendered":"Building a 20 meter self-tuning magnetic loop antenna"},"content":{"rendered":"

\"Magnetic<\/a><\/p>\n

I’m often asked about what’s involved with building a home brew magnetic loop antenna.<\/p>\n

If you’re considering building a passive loop antenna–one designed to both transmit and receive without any sort of receiver amplification–it’s a simple project. With basic DIY skills, a little math, a good variable capacitor, some copper tubing or coax, and a few inexpensive parts, it’s easy to make a passive antenna designed to operate on a given portion of the HF spectrum. It can be an easy two hour build as long as you have all of the parts. There are a number of tutorials for doing this on the web and several books on the topic (one of my favorites is Joe Carr’s Loop Antenna Handbook<\/a>).<\/p>\n

The compromise with a passive loop design is that they tend to have a very narrow bandwidth. In other words, you might have to re-tune the antenna via the variable capacitor even if you only move the frequency 5-10 kHz or so.<\/p>\n

Via Hackaday<\/a>, I recently discovered this innovative self-tuning passive loop antenna design by Eric Sorensen. Eric implements a stepper motor to make tuning adjustments. Not necessarily a beginner’s project, but the principles are straight-forward. He even includes a link to his printed components.<\/p>\n

Click here to view Eric’s 20 meter loop antenna project.<\/a><\/strong><\/p>\n","protected":false},"excerpt":{"rendered":"

I’m often asked about what’s involved with building a home brew magnetic loop antenna. If you’re considering building a passive loop antenna–one designed to both transmit and receive without any sort of receiver amplification–it’s a simple project. With basic DIY skills, a little math, a good variable capacitor, some copper tubing or coax, and a […]<\/p>\n","protected":false},"author":15,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"jetpack_post_was_ever_published":false,"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_publicize_message":"","jetpack_publicize_feature_enabled":true,"jetpack_social_post_already_shared":true,"jetpack_social_options":{"image_generator_settings":{"template":"highway","default_image_id":0,"font":"","enabled":false},"version":2}},"categories":[3607,627,3],"tags":[4357,5985,3417],"class_list":["post-36661","post","type-post","status-publish","format-standard","hentry","category-antennas","category-how-to","category-news","tag-mag-loop-antennas","tag-magnetic-loop","tag-magnetic-loop-antennas"],"jetpack_publicize_connections":[],"jetpack_featured_media_url":"","jetpack_shortlink":"https:\/\/wp.me\/pn3uc-9xj","jetpack-related-posts":[{"id":50098,"url":"https:\/\/swling.com\/blog\/2021\/08\/wire-antennas-vs-mag-loop-antennas\/","url_meta":{"origin":36661,"position":0},"title":"Wire antennas vs. mag loop antennas","author":"Thomas","date":"August 29, 2021","format":false,"excerpt":"In the past few weeks, I've gotten a lot of questions from readers who are trying to decide if they should install a magnetic loop antenna or a simple wire antenna at their home. Obviously, most of the questions come from shortwave radio listeners, but some have come from ham\u2026","rel":"","context":"In "Antennas"","block_context":{"text":"Antennas","link":"https:\/\/swling.com\/blog\/category\/antennas\/"},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/swling.com\/blog\/wp-content\/uploads\/2014\/06\/Elecraft-KX3.jpg?resize=350%2C200&ssl=1","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/swling.com\/blog\/wp-content\/uploads\/2014\/06\/Elecraft-KX3.jpg?resize=350%2C200&ssl=1 1x, https:\/\/i0.wp.com\/swling.com\/blog\/wp-content\/uploads\/2014\/06\/Elecraft-KX3.jpg?resize=525%2C300&ssl=1 1.5x"},"classes":[]},{"id":39811,"url":"https:\/\/swling.com\/blog\/2019\/09\/marty-needs-advice-as-he-builds-a-passive-magnetic-loop-antenna\/","url_meta":{"origin":36661,"position":1},"title":"Marty needs advice as he builds a passive magnetic loop antenna","author":"Thomas","date":"September 25, 2019","format":false,"excerpt":"Many thanks to SWLing Post contributor, Marty Kraft, who asked that I share the following question with our community: I\u2019m still working on a receive-only passive hula loop magnetic antenna for my Tecsun PL-660. After viewing thousands of YouTube videos (LOL), I built the PVC-pipe structure [you can see in\u2026","rel":"","context":"In "Antennas"","block_context":{"text":"Antennas","link":"https:\/\/swling.com\/blog\/category\/antennas\/"},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/swling.com\/blog\/wp-content\/uploads\/2019\/09\/Loop-antenna.jpg?resize=350%2C200&ssl=1","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/swling.com\/blog\/wp-content\/uploads\/2019\/09\/Loop-antenna.jpg?resize=350%2C200&ssl=1 1x, https:\/\/i0.wp.com\/swling.com\/blog\/wp-content\/uploads\/2019\/09\/Loop-antenna.jpg?resize=525%2C300&ssl=1 1.5x"},"classes":[]},{"id":28543,"url":"https:\/\/swling.com\/blog\/2017\/09\/larrys-variation-of-the-w6lvp-amplified-magnetic-loop-antenna\/","url_meta":{"origin":36661,"position":2},"title":"Larry’s variation of the W6LVP amplified magnetic loop antenna","author":"Thomas","date":"September 28, 2017","format":false,"excerpt":"Many thanks to SWLing Post contributor,\u00a0Larry Thompson (WPE8EKM), who writes: I\u2019ve just finished building a variation of the W6LVP amplified magnetic loop antenna. I was able to purchase the preamplifier, power inserter, and the power supply separately. I then created my own loop antenna using LMR400Max coax and designed my\u2026","rel":"","context":"In "Antennas"","block_context":{"text":"Antennas","link":"https:\/\/swling.com\/blog\/category\/antennas\/"},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/swling.com\/blog\/wp-content\/uploads\/2017\/09\/Loop-Antenna.jpg?resize=350%2C200&ssl=1","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/swling.com\/blog\/wp-content\/uploads\/2017\/09\/Loop-Antenna.jpg?resize=350%2C200&ssl=1 1x, https:\/\/i0.wp.com\/swling.com\/blog\/wp-content\/uploads\/2017\/09\/Loop-Antenna.jpg?resize=525%2C300&ssl=1 1.5x"},"classes":[]},{"id":31920,"url":"https:\/\/swling.com\/blog\/2018\/05\/bill-scores-a-homebrew-lw-mw-magnetic-loop-antenna\/","url_meta":{"origin":36661,"position":3},"title":"Bill scores a homebrew LW\/MW magnetic loop antenna","author":"Thomas","date":"May 7, 2018","format":false,"excerpt":"Many thanks to SWLing Post contributor, Bill Hemphill (WD9EQD) who shares the following: I went to the Warminster Amateur Radio Club (WARC) hamfest [yesterday] in Bucks County, PA. For some time, I have been thinking about making a loop antenna for AM DXing. It was my lucky day. When I\u2026","rel":"","context":"In "AM"","block_context":{"text":"AM","link":"https:\/\/swling.com\/blog\/category\/am\/"},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/swling.com\/blog\/wp-content\/uploads\/2018\/05\/Mag-Loop-Antenna-Homebrew-1-777x1024.jpg?resize=350%2C200&ssl=1","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/swling.com\/blog\/wp-content\/uploads\/2018\/05\/Mag-Loop-Antenna-Homebrew-1-777x1024.jpg?resize=350%2C200&ssl=1 1x, https:\/\/i0.wp.com\/swling.com\/blog\/wp-content\/uploads\/2018\/05\/Mag-Loop-Antenna-Homebrew-1-777x1024.jpg?resize=525%2C300&ssl=1 1.5x"},"classes":[]},{"id":38451,"url":"https:\/\/swling.com\/blog\/2019\/07\/using-amplified-loop-antennas-with-portable-radios\/","url_meta":{"origin":36661,"position":4},"title":"Using amplified loop antennas with portable radios?","author":"Thomas","date":"July 11, 2019","format":false,"excerpt":"Many thanks to SWLing Post contributor, Marty, who writes: I have a question about loop antennas; specifically which type is \"better,\" passive magnetic loops or active electric loops? I know, \"It depends.\"--? I live in a ground-floor apartment, with a small porch, lots of RFI and restrictions against visible antennas.\u2026","rel":"","context":"In "Antennas"","block_context":{"text":"Antennas","link":"https:\/\/swling.com\/blog\/category\/antennas\/"},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/swling.com\/blog\/wp-content\/uploads\/2017\/01\/Klaus-Mag-Loop-Antenna.jpg?resize=350%2C200&ssl=1","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/swling.com\/blog\/wp-content\/uploads\/2017\/01\/Klaus-Mag-Loop-Antenna.jpg?resize=350%2C200&ssl=1 1x, https:\/\/i0.wp.com\/swling.com\/blog\/wp-content\/uploads\/2017\/01\/Klaus-Mag-Loop-Antenna.jpg?resize=525%2C300&ssl=1 1.5x, https:\/\/i0.wp.com\/swling.com\/blog\/wp-content\/uploads\/2017\/01\/Klaus-Mag-Loop-Antenna.jpg?resize=700%2C400&ssl=1 2x"},"classes":[]},{"id":30672,"url":"https:\/\/swling.com\/blog\/2018\/02\/indoor-shortwave-antenna-options-to-pair-with-a-new-sdr\/","url_meta":{"origin":36661,"position":5},"title":"Indoor shortwave antenna options to pair with a new SDR","author":"Thomas","date":"February 9, 2018","format":false,"excerpt":"Many thanks to SWLing Post contributor, Chris Freitas, who writes: \"I am thinking of the new RSP1A SDR. Would you know of a good indoor antenna that would work well with it?\" Your antenna question is simple, but the answer is complex! First off, I think the RSP1A is a\u2026","rel":"","context":"In "Antennas"","block_context":{"text":"Antennas","link":"https:\/\/swling.com\/blog\/category\/antennas\/"},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/swling.com\/blog\/wp-content\/uploads\/2017\/11\/RSP1A1-1024x708.jpg?resize=350%2C200&ssl=1","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/swling.com\/blog\/wp-content\/uploads\/2017\/11\/RSP1A1-1024x708.jpg?resize=350%2C200&ssl=1 1x, https:\/\/i0.wp.com\/swling.com\/blog\/wp-content\/uploads\/2017\/11\/RSP1A1-1024x708.jpg?resize=525%2C300&ssl=1 1.5x, https:\/\/i0.wp.com\/swling.com\/blog\/wp-content\/uploads\/2017\/11\/RSP1A1-1024x708.jpg?resize=700%2C400&ssl=1 2x"},"classes":[]}],"jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/swling.com\/blog\/wp-json\/wp\/v2\/posts\/36661","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/swling.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/swling.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/swling.com\/blog\/wp-json\/wp\/v2\/users\/15"}],"replies":[{"embeddable":true,"href":"https:\/\/swling.com\/blog\/wp-json\/wp\/v2\/comments?post=36661"}],"version-history":[{"count":0,"href":"https:\/\/swling.com\/blog\/wp-json\/wp\/v2\/posts\/36661\/revisions"}],"wp:attachment":[{"href":"https:\/\/swling.com\/blog\/wp-json\/wp\/v2\/media?parent=36661"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/swling.com\/blog\/wp-json\/wp\/v2\/categories?post=36661"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/swling.com\/blog\/wp-json\/wp\/v2\/tags?post=36661"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}