I suggest that you buy a WWVB module and adjuat the frequency slightly with a new crystal. WWVB is a time/date signal from Ft Collins, CO USA sending at 60.00khz. The modules are available from Digikey for about $10 USD. --Bob A On Mon, Jan 2, 2012 at 11:12 PM, fred jones wrote: > > Hi all, > =A0I have a question for those analog engineers on the list. =A0I have be= en searching the internet for information on listening to ELF signals. =A0I= have found some information but not exaxtly what I'm looking for. =A0For e= xample one site has a circuit of amplifiers and passive filters utilizing e= ither an antenna or just probes stuck in the ground to receive ELF signals = below 50Hz. =A0Another person has a very large coil of wire wound on a spoo= l and just sets it on the ground. =A0What I would like to do is similar but= I'd like to listen to 76Hz which is the US submarine communications freque= ncy. =A0The Russians utilize 82Hz. =A0Is it possible to build a circuit tha= t would pickup the 76Hz signal only? =A0Any information on how to do this i= f it is possible is appreciated. > Thanks, > FJ > > http://www.vlf.it/kurt/elf.html > -- > http://www.piclist.com PIC/SX FAQ & list archive > View/change your membership options at > http://mailman.mit.edu/mailman/listinfo/piclist --=20 http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .