Oscar-Zero Missile Alert Facility Minuteman ICBM Launch Control (Wikimedia Commons)
Many thanks to SWLing Post contributor Dennis Dura, who shares the following article about Cold War–era low-frequency communications, from Hackaday:
During the Cold War, the U.S. developed the Survivable Low-Frequency Communication System (SLFCS) — 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’s immense towers and buried loop antennas reflect an era when reliability was paramount — even under atomic conditions.
