Yaa, you would think that an I/O card (with the TC voltage coming in
and the voltage to the relay going out) could do this pretty easily and
you could just put in the "curve" you want in your PC program and it
would know how to get you there. Basically a PC software driven PID
using a cheap I/O card off the RS232.

I did a brief look but couldn't find anything though so it's no doubt
harder than I'm imagining it.

I did find some cool stuff on guys doing their own coffee roasting with
hot-air popcorn poppers They're using PIDs too.

Joe