In a message dated 11/29/99 11:17:37 AM Eastern Standard Time,
k3jsch@MAIL.GMTCOM.COM writes:

> I am looking at a simple 4-20mA transmitter circuit that I need for an
>  industrial application.  Preferably, I am looking to do it with some form
>  of op-amp based circuitry. It is important to state at this time that the
>  Burr-Brown and Datel special purpose 4-20mA ICs have been ruled out due
>  to their expense.
>
>  Any help given would be appreciated.
>
>  Thank you,
>
>  Kelly Schauf
>
Why not use an op amp with the 4-20 ma loop in the feed-back of the op amp?
That works well if you do not require isolation.

Max