Shortwave Logbook

Mexican music, full ID as "Radio México Internacional...XERMX", frequencies given, talk. Propagation Notes: Reception occurred during the major geomagnetic storm of 13–14 July 1982, one of the strongest of Solar Cycle 21 (minimum Dst ≈ −325 nT). A rapid increase in solar wind dynamic pressure caused a widespread depletion of the F2-layer critical frequency (foF2), significantly reducing maximum usable frequencies on many paths. Despite generally poor shortwave propagation, southward paths into Mexico and South America remained open, allowing reception of Radio México Internacional (15430 kHz), RAE (11710 kHz), Radio El Mundo (11755 kHz), Radio El Espectador (11835 kHz), and XEQM Mérida (6105 kHz). All signals exhibited pronounced flutter and rapid fading, resembling auroral/polar flutter, consistent with severe ionospheric disturbances during the storm. Source: Burešová, D., et al., A study of the geomagnetic storm of July 13–14, 1982, and its ionospheric response, Contributions to Geophysics and Geodesy, Vol. 37, No. 3, 2007. https://link.springer.com/article/10.2478/s11600-007-0030-6