UNI-T UT50C multimeter calibration, tests, bugs, etc.

[cosmin1]

Hello.
I want to calibrate my UT50C, but don't know which trimmer for which domain.

LE: i identified some of them.
Here is what i have:
VR1 - DC voltage
VR2 - Capacitance
VR3 - AC voltage
VR4 - ?
VR5 - ?
VR6 - Temperature °F
VR7 - Temperature °C
VR8 - Frequency
VR9 - ?



I really like this multimeter.
It's really simple and i appreciate the ON\OFF button and automatic lighting. I hate the timed lighting on other models. On this one, the light is there exactly when you need it.
Anyway, i don't intend to work with itmin high voltage equipments. In rare cases, maximum 230V.

[cosmin1]

I succeeded.

[cosmin1]

On the other hand, the multimeter has a bug.
Measuring a 22k resistor on the 200Mohm scale, indicates 1Mohm value. Changing to a lower scale and measuring the same resistor, shows the real value.
May be a model bug or just this multimeter is somehow defective?

[Chris56000]

Hi!

I gave my Band Musician friend Mike Smith one of these models and I found it does indeed have this bug on the 200M resistance range –  not only that, but the one I gave away always showed "001.0" on the 200M range even on open–circuit!

I think UNI–T have made a design howler and somehow shunted a fixed 1M into the top 200M range, possibly a design defect in the DVM chip itself!

Is there a schematic available?

Chris Williams
This