>I wonder if you have considered active low pass filters?
>
>I have achieved some pretty impressive ripple rejection
>by adding either a emitter follower capacitance amplifier
>or a low pass op-amp.

I have been puttering around with op-amps.  It'll be my next attempt, if
the way I have it set up now doesn't work.

I take it you're thinking setup a +/- 7 or 8 volt input from the noisy 12V,
then use something else to make a precision +/- 5 V ref and run the
signal from those references thru the LPF?  I like the idea in theory, but
in practice, I'm starting to end up with a big honkin' PCB for what SHOULD
be a tiny lil' circuit.

But if that's the way it works, that's the way it needs to be done.

Mike H.

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