On Tue, Feb 15, 2011 at 2:14 PM, Andre Majorel <aym-htnys at teaser.fr> wrote: > Do you folks have any recommendations for phase reversal-free, > high input impedance op amps ? > LM324? Tim (reasonably sure) Servo -- "Sire, the church of God is an anvil that has worn out many hammers." - H.L. Hastings