{"id":64588,"date":"2025-11-13T08:26:55","date_gmt":"2025-11-13T12:26:55","guid":{"rendered":"https:\/\/swling.com\/blog\/?p=64588"},"modified":"2025-11-13T08:26:55","modified_gmt":"2025-11-13T12:26:55","slug":"hackaday-the-cold-war-era-survivable-low-frequency-communication-system-slfcs","status":"publish","type":"post","link":"https:\/\/swling.com\/blog\/2025\/11\/hackaday-the-cold-war-era-survivable-low-frequency-communication-system-slfcs\/","title":{"rendered":"Hackaday: The Cold War-Era Survivable Low-Frequency Communication System (SLFCS)"},"content":{"rendered":"
\"\"<\/a>

Oscar-Zero Missile Alert Facility Minuteman ICBM Launch Control (Wikimedia Commons)<\/p><\/div>\n

Many thanks to SWLing Post<\/em> contributor Dennis Dura, who shares the following article about Cold War\u2013era low-frequency communications, from Hackaday:<\/strong><\/p>\n

During the Cold War, the U.S. developed the Survivable Low-Frequency Communication System (SLFCS) \u2014 a radio network designed to function even after a nuclear attack. Using long-wavelength LF and VLF signals that can travel vast distances through ground and ionospheric waveguides, SLFCS provided a way to deliver emergency launch orders when all else failed. The system\u2019s immense towers and buried loop antennas reflect an era when reliability was paramount \u2014 even under atomic conditions.<\/p>\n

Read the full article on Hackaday by clicking here.<\/a><\/strong><\/p>\n","protected":false},"excerpt":{"rendered":"

Many thanks to SWLing Post contributor Dennis Dura, who shares the following article about Cold War\u2013era low-frequency communications, from Hackaday: During the Cold War, the U.S. developed the Survivable Low-Frequency Communication System (SLFCS) \u2014 a radio network designed to function even after a nuclear attack. Using long-wavelength LF and VLF signals that can travel vast […]<\/p>\n","protected":false},"author":15,"featured_media":0,"comment_status":"open","ping_status":"closed","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":[3,288],"tags":[3067,5875,3354,10963],"class_list":["post-64588","post","type-post","status-publish","format-standard","hentry","category-news","category-radio-history","tag-cold-war-radio","tag-dennis-dura","tag-hackaday","tag-survivable-low-frequency-communication-system-slfcs"],"jetpack_publicize_connections":[],"jetpack_featured_media_url":"","jetpack_shortlink":"https:\/\/wp.me\/pn3uc-gNK","jetpack-related-posts":[{"id":62933,"url":"https:\/\/swling.com\/blog\/2025\/05\/meteor-burst-communications\/","url_meta":{"origin":64588,"position":0},"title":"Meteor Burst Communications","author":"Thomas","date":"May 13, 2025","format":false,"excerpt":"Many thanks to SWLing Post contributor, Dennis Dura, for sharing the following article from Hackaday: Radio Apocalypse: Meteor Burst Communications This piece explores Meteor Burst Communications (MBC)\u2014a method of bouncing radio signals off ionized meteor trails to enable long-distance communication without relying on satellites or infrastructure. 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What you may have missed, though, is the hacker\/ham radio connection. 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