I agree that this isn't necessarily the place for waving technological hurricane warnings, but the phenomenon, as you probably know, is real. It was part of the nuclear strategies of both sides during the cold war to burst warheads high over each others' countries to take out solid-state communications systems. Interestingly, for communications purposes, the one technology that seemed much less vulnerable to electromagnetic pulse was tube technology. And for communications, who had the largest inventory of tube-based communications gear? Ham radio operators. Ah, there's something to be said for the good old days ;-) With best regards, Pete -- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Peter N. Spotts | Science Correspondent The Christian Science Monitor One Norway Street, Boston MA 02115 Office: 617-450-2449 | Office in home: 508-520-3139 Email: pspotts@alum.mit.edu | www.csmonitor.com ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~