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| Joined: | Sep 22nd, 2008 |
| Location: | Doylestown, Pennsylvania USA |
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mikesndbs wrote:
Hi Joe
Been thinking about this today and have done some hook ups to check.
If I remove the choke from the diagram and instead use the 100K resistor in its place so as to give me a circuit, I hear mostly a 50hz hum from the mains here in the UK.
Could I filter this using passive components, but still keep this 'sniffer' sensitive to all other fqs?
Thanks
Mike
Mike,
Look at this circuitry for a way to boost vlf signals and reduce the power hum. This design is essentially an untuned radio receiver with vlf bandwidth. The filter cuts the hum.
http://www.auroralchorus.com/bbb4rx3.htm
Joe