Brymen BM789: Not a Review
Almost two years ago I bought a Brymen BM789 Multimeter. And there is a lot to like about it. It has great specs, is feature-packed, feels high-quality and yet it’s well priced. But there are also some mostly minor aspects I don’t like: The segments of the display on my unit vary in contrast slightly but noticably - especially with backlight - like the zebra strip wouldn’t provide the best connection. It’s not that. You might be able to see it on the cover picture. With the backlight enabled and depending on the viewing angle, the contrast isn’t too great either, a characteristic it shares with many other multimeters (Hello Fluke 170 series) Brymen had to ship multiple versions of the firmware to fix some issues, some of which might have to do with part tolerances and therefore aren’t relevant for all units. The current version is 78911, mine was one of the earlier units and shipped with version 78905 - supposedly the first mass-deployed firmware. I didn’t notice any issues on my unit and many of the problems are likely solved by now. To change the fuses you have to open the meter (like with many, but not all other meters) My personal opinion: The Fluke 170 series is easier to work on. But it doesn’t have nearly as many features either ( and therefore components and boards) My main issue though and this is not limited to Brymen (hello Hameg, Rohde & Schwarz, Keysight): I couldn’t find any calibration/adjustment procedure. In my case I’m interested in calibrating and adjusting the low DC and AC voltage ranges. Given an adjustable and reasonably low noise source and a decent (calibrated) 6.5-digit multimeter this is something even more serious hobbyists could do reasonably well. It’s possible to figure out how it’s done, but why did I have to? Didn’t I buy the meter? ...
