I have found a couple schematics for low pass and high pass opamp filter, I =
would like to run them from single +5V supply and am concerned that the singals =
will be wanting to go above and below ground, but I have no negative supply.

The schematics can be found on this page =
http://ourworld.compuserve.com/homepages/Bill_Bowden/opamp.htm

Once the signal enters through a cap the DC offset is lost, how do you make =
sure the signal stays around say 2.5V of the 5V supply?

Richard.

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