On Mon, 9 Jan 2006, David VanHorn wrote: > On 1/9/06, lucid@magnet.ca wrote: >> >> 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. > > Things get pretty interesting down there. The PC itself is a loud noise > source. > > Look at what's done for "Whistlers" and ELF reception, should give you some > ideas. Hehe. I just restored an old valved radio to life. I can use it next to the computer just fine (can't do that with a SONY ICF-SW11). Totally imprevious to RFI from the computer. With about 75V headroom I can understand that ... it's a nice portable from the 1950's with instant on (direct heated filaments). I am listening to it now (DX on AM). It is more sensitive with its 4 valves (some are double) than the ICF-SW11 and sounds better too. Just one problem: I don't think it has an AGC ... As to logging with a PC, it should be no problem as long as the receiver is coupled with optical fiber to the PC. I have been trying to get to do this using inexpensive 'miniplug' (SPDIF) fiber cable but it is still on the to-be-done list. Some day soon ... in fact this thread may bring it closer. thanks, Peter -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist