My BSIDE ZT301 arrived today.
Very impressive - that only took 2 weeks from China. Excellent service! Wish I could say the same of the seller who apparently sent me a UNI-T UT139C at the start of October, but it'll be OK in the end, I'm sure...
I haven't had a chance to test it properly, but here are some initial impressions.
The first pictures shows it between the AN8002 and the AN860B+. As you can see, it's quite a bit smaller than the latter - more so than the dimensions suggested. It doesn't have the rubber holster that the AN860B+ has, being the same construction as the AN8002.
Inside, we see 20mm ceramic fuses. Everything else is as expected for these meters - the COB and EEPROM, some MELF resistors for the current shunts and two 5M resistors that set the 10M input impedance. Of course, there is the expected minimal input protection. The silk screen says ZT301 V0.1, with a 2017 date code, so this is a pretty new design. The electrolytic cap is not a Rubycon - it's a Chang. Note how the battery holder has been shaved to clear a couple of resistors, that will almost certainly get moved when the PCB is next revised.
Underneath the PCB is almost nothing. But they did grease the switch tracks. And it feels like they greased the range switch, which feels really nice compared to all the other cheap meters I've tested.
In use, the meter works as well as expected. I was extremely pleased to discover that the backlight timeout is a sensible 2 minutes, rather than the silly 15 seconds I'm used to seeing with these cheap meters. More exploration is needed, but the only "quirk" I noted is the Hz/% selection: on the dedicated Hz position of the range switch, you need to press the button labelled "Hz/%", which is fair enough, but on the other switch positions that allow Hz/%, you get at that by pressing the yellow Select button - in which case, the Hz button does nothing. With the AN860B+, the Hz/% button always selects frequency and duty cycle, providing you're in a suitable AC mode. It's a small niggle, and you'd get used to it - not a deal breaker.
The best voltage resolution is 10uV, not the 1uV of the AN8008. But at least it does more than 10M - the highest range is 80M. The uA range has 0.1uA resolution.
The display is good. The contrast isn't great when viewed at 90 degrees, but when lying on the bench, it's nice and clear. The unlit segments stay unlit even at low angles - unlike the AN860B+, which I can't lie down on the bench if I wish to use it.
The final picture is really interesting. It shows the rear of the box, and implies there are 2 more meters in this series - one has a 9999-count (almost certainly the ZT302), and the other is a 19,000-count! If this comes true, then I wonder what chipset they're using? Can the DM1106EN used in the AN8008 (and probably this model - rather than the DTM0660?) be hacked to give 19,999 counts? I know that's of no use to those with meters that only have 4 digits on their LCDs, but it does open the door to a whole range of new, cheap meters with higher counts. Interesting...
The test leads are the same type that you get with the Aneng meters. A bit small, but pretty flexible, so quite usable in practice. Usually with BSIDE meters, the leads are far too stiff to be of any practical use. The sockets are a bit shallow, so while better quality leads will work electrically, they will stick out of the front panel somewhat. The package also includes the standard cheap thermocouple and the manual. But no carry-bag with this one!
Anyway, it's going to take a while to get around to a full review, but hopefully this is of interest in the meantime. If there are any questions, do shout!