>>a discrete circuit. The author proposes that a 4 npn diff amp makes a >>resonable good converter. >> >>Any comments ? >Moog Modular. >JH. Yes, the converter in the 921B works well. I built it recently, but I haven't had a 3080-based one for comparison, so I can't say which is better. The Moog circuit uses four transistors from a CA3046. /Jorgen