Re: Op amp input R to gnd., caps for anti-alias filters Q's

Hello John, Hello Dave,


You can buy 1% NPO caps.


If that is still too much you can add varicap diodes, the ones for AM band radios. But you'd need at least 10V from somewhere for a full range and something has to control that neutralizing process, ideally a multi-output DAC and some firmware. Trimpots and trim caps are another option but not too reliable IMHO.

Regards, Joerg

http://www.analogconsultants.com
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