Hey Guys,
Just got to try an old Idea i learned a long
time ago but never tried.

If you dont have a big 3Meg resistor to go
with that 1u condensor for your op amp filter
just string together three attenuators in series
that are like this

  AmpOut--R6800--R--6800--R--6800--R--AmpMinusInput
                 3        3        3
                 3        3        3
                 0        0        0
                 G        G        G

Then put the 1U cap across all three 6800 ohm resistors

it works like this

((1/(330/(6800 + 330)) ^ 3) * 330) for the equivelent resistance in ohms

like ==> 3,328,440 ohms with your 1u poly condensor

im using this now in my circuit. just never tried it before.

thats about a  1/20.9 hertz.

lpf equalization.

regards
geoff
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