Re: ELF detector

From: Ken Smith (kensmith_at_green.rahul.net)
Date: 09/26/04 

Date: Sun, 26 Sep 2004 18:51:32 +0000 (UTC)

In article <4156700E.AD098E76@earthlink.net>,
Robert Baer <robertbaer@earthlink.net> wrote:
>Ken Smith wrote:
>>
[...]
>> You didn't give enough details. How big does the loop have to be to do
>> the "0-" part of the range?
>>
>> --
>> --
>> kensmith@rahul.net forging knowledge
>
> Depends on the sensitivity you want.
> Obviously, you cannot make a loop any where near 1/4 wavelength...

When you go to normalize the gain of the induction loop at zero Hz, you
have to write some very tricky software. You have to divide by zero to
get any sensitivity you want. Most programmers would have trouble
designing a divide by zero routine that is accurate to more than 1 bit.

You could use a GMR or other magnetoresistive device. 

-- 
--
kensmith@rahul.net   forging knowledge

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