On Tue, 26 May 1998 21:03:50 -0400 Andy Kunz writes: >I was thinking that this is an ideal situation for using an >opto-isolator, >and was wondering if anybody knew in a practical way if this would >provide >reasonable accuracy with varied temps, etc. > I think CP Claire (or something like that) has an opto designed for linear operation. As I recall, there might be two LEDs and two detectors that are matched so you can get rid of nonlinearities by putting stuff in an op-amp feedback loop. They've also got some telephone DAAs that don't use a transformer, which is pretty neat! Harold _____________________________________________________________________ You don't need to buy Internet access to use free Internet e-mail. Get completely free e-mail from Juno at http://www.juno.com Or call Juno at (800) 654-JUNO [654-5866]