New meter arrived the other day, bought cheap and not working once more.
(Paying the price for working equipment takes the fun out of it, and is not worth the bother half the time, as things come with problems even when sold as working...)
It was was making a rattling sound so I didn't turn it on, I took it apart.
Found a loose melf diode floating around, a close look made it obvious where is came from, et voilĂ ! Another working meter in the heap.
Now the downside: Metrix was one of the reference brands for meters in France, they have since been bought out by Chauvin-Arnoux who still sell Metrix and Multimetrix branded meters.
Metrix / Multimetrix seem to have been moved down to the low-end, the Chauvin-Arnoux being the serious stuff. (I wish someone would review / teardown the Metrix Scopix III handheld scopes here!)
The build quality of this megohmmeter is just way under what I was expecting from Metrix, clearly a Chinese job, the "QC" sticker was on the back but components drop-off the PCB from being only half soldered.
The ADC is a GC7135, equivalent to the ICL7135 but there again, a little deceiving, as it is the cheap far-east copy.
The PCB is marked "Meiyad" just under the transformer so possibly none of the design is done by Chauvin-Arnoux at all.