SInce I sometimes take testing fairly seriously, I have several meters with several slightly different diode testing modes. I've found none which indicate a bad diode is good, nor do any of them indicate a good diode is bad. One of my testers is something I built for matching diodes, and and transistors, and it runs a pretty constant 1.26 or 12.6 ma (from an LED biasing a 2N3904) through a diode, and a panel meter displays the forward voltage. Not one of my meters exhibits behavior as described by "Wizard" however. I can't imagine what the problem is, but I agree that digital meters can produce unpredictable results when used in a way not intended by the designers. Generally speaking, the DMM is a Digital Panel Meter with a fixed reference voltage built into it, looking a the output of an analog or even mechanical switch, the purpose of which is to run the appropriate current through/into the component under test to generate a voltage scaled to display a value reflecting the value of the component under test. In the case of diode test, that's really easy, since it's a current within a fairly forgiving range, and which will, with most any diode produce a voltage reflecting what that particular diode drops at that current. Almost all measurements can easily be done in this way. Voltage is easiest, of course. Dick -----Original Message----- From: sms(a)antinode.org <sms(a)antinode.org> To: Discussion re-collecting of classic computers <classiccmp(a)u.washington.edu> Date: Wednesday, November 03, 1999 4:40 PM Subject: Re: schottky diode again.. as though