cpat, i'm sure you have figured out by now you are barking up the wrong tree. we are not designers and rarely use software. you design based upon constants in books. we verify a system is running according to your specs and if it is not, we correct it. you need to consult with your colleagues, your libraries and your software designers. no offense intended, but if you are in the middle of a final software design, it seems a little late to be gathering field input from technicians. if you need field input, your lab is the building you are modifying.