Hi guys. In my quest for accurate measurement, I would like to find out if I could find somewhere the calibration procedure for the UEI DM397 DMM. This DMM is not perfect as most of you know, but out of the box it has nice specifications. I scored one brand new one a year and half ago for a ridiculous price, and I am quite pleased with it, apart from few ergonomic glitches. Now I've tried to measure a reference voltage source that I got, and against other DMM I own. It appears to be slightly out of specs at least on DC voltages. As this DMM has a good resolution, and supposedly an excellent precision of 0.05% on most DC ranges, I was wondering if someone knew the procedure to calibrate it. As it is stated to have a "closed case" calibration (lol), it must be some sort of tweaks at start up, pressing and holding some buttons. Most recent UEI DMM probably share the same procedure, so if someone knows how to enter the calibration mode on one other model, let me know. From what I've read on this forum, UEI does not provide this type of documentation. I have asked BK Precision the same procedure a few weeks ago, and they sent it to me without any problem... "Some brands are bigger than others" as the Moz would say...
Thanks for you help !!