LONG-DELAY RADIO ECHOES: During the geomagnetic storm of Nov. 27th, a brief but intense G2-class event, amateur radio operator Peter Brogl of Fürth, Germany experienced a strange phenomenon. Forty-six seconds after he transmitted his call sign at 7 MHz, he received an echo of his own transmission. "At first, I thought someone was playing tricks on me," says Brogl, "but I changed frequency, re-keyed my call sign (DK6NP), and got another echo." This went on for more than an hour, enough time for Brogl to make several recordings. First reported in 1927 by Norwegian civil engineer Jørgen Hals, long-delay radio echoes are rare and poorly understood. Unusual propagation conditions linked to solar storms is one of many possible explanations.*
*from Spaceweather.com front page (a recording of his echo is also there).
*from Spaceweather.com front page (a recording of his echo is also there).