I was reading a thread about repairing a Tek scope recently, and a number of members were warning about tek's use of proprietary ( now obsolete ) IC's in their products. I recently repaired of of these scopes, and was fortunate enough to not need one of these devices. Anyway, I was wondering about the possibility of using a PIC or CPLD in place of some of these IC's. One might even be able to ascertain the chip's function by analyzing the circuitry around it, or by probing a working unit. Has anyone ever tried this? What were the results?