Since I can not find a review of the meter, I will post what I can.
The case is very ridged, and like the selector switch feels quite nice, but not as nice as a fluke. No annoying beeps/music, etc and it's auto-range is pretty decent, but kicks in a little early when on ohms and measuring a 95-99k resistor, setting the range manually though allows you to gain the additional precision.
It has a nice fast update, I like the large digits and it has a nice and quick display update. It does not seem to suffer from any of the firmware issues the other models have experienced. It allows you to check the battery level which is nice, but I also found an undocumented feature where if you hold the back-light button and the Hz button when turning it on, it will show you the battery voltage. Not sure why they do not allow you to see this on the documented BAT feature.
The rear stand seems to be made of a very weak inflexible stand as evidenced by the broken cross-member and does not feel well made at all. It runs on 4x AAA, but fuses are not accessible without taking the back off the meter (which is a little strange as there is room for it, and the battery cover has enough room to have allowed them to have provided access to the 440mA fuse). The battery cover has a captive screw which is nice, and uses a threaded insert.
The case has 4 long threaded screws with threaded inserts which is very nice
. To gain access to the 11A fuse you need to fully dismantle the unit
, which involves removing the 440mA fuse
, and 4 self tappers, so a bit of a chore to get to it should it need changing. A small worry is that one of the threaded screws that hold the terminal post daughter board, which is also the connection for the micro amps input is about 3mm from the 440mA fuse holder terminal
.
Internal contacts are all gold plated, and has good input protection via heavy 0.1k resistors, PTCs, and then connected to some AG20 TAYIO Ceramic Resonators. The micro is a Samsung S3P825 80pin TQFP with a 2.4576Mhz crystal and uses a TI ADS1242 (24-Bit Analog-To-Digital Converter). The board also has a Atmel 24C64 (64K (8192 x
2-wire Serial EEPROM).
I can not see any unpopulated components inside, so I would suspect that you could upgrade this unit to a U1242 with a firmware change, possibly via the EEPROM, but I suspect the EEPROM is just for user settings and value storage.
Edit: The S3P825A is a microcontroller with a 48K-byte one-time-programmable ROM embedded. So if it does allow for firmware updates, it could very well be possible that it is in the Atmel EEPROM.
Edit2: The 440mA fuse holder is around 1mm to the screw when the fuse is installed.
Edit 4: I have confirmed that the EEPROM contains the model identifier for the meter, by shorting out the SCL and SCA lines the meter powers up and has all the features of the U1242 . Now to dump the EEPROM and see if I can make this change properly.