Can anyone guide me towards a relatively budgetary solution (ideally PC based) for logging a broad spectrum or multiple narrower spectrums of Extra Low Frequency electro-magnetic radiation in the .01-2000 Hz range? Something like a simple card for PC with external antenna of some sort would be great. Thanks, TC -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist