In my experience (of a single T7 version), it has been fine…
…Had a look inside
Thanks for the PC board photos of your
LCR-T7. Your unit contains a genuine Atmel
ATmega324 MCU. This is confirmed by the MCU chip having 11 pins on each side, 44 pins total. This 44 pin package is unique to the Atmel MCU chip family which includes the
ATmega324 and the
ATmega644 .
The other Atmel MCU chip frequently used in transistor testers (
ATmega328 ) has 8 pins on each side, 32 pins total.
To the best of my knowledge all of the alternate Chinese MCU chips recently showing up in transistor testers also have 32 pins. Some are (deliberately) mislabeled as ATmega328. However their pinout and internal functionality is completely different.
The Chinese manufacturers have cobbled together their own proprietary firmware. Its quality varies:
1) Usually several of the expected transistor tester features are missing
2) Some measurement results may be very inaccurate
3) It is impossible to upgrade or replace this proprietary firmware
At this time
none of the extensive library of open-source transistor tester software/firmware supports
any of these alternative Chinese MCU chips.