Up to now my DT830B is still running, but i’m not using anymore. Because now i’m using higher model from UNI-T

I am aware that DMM prices had been steadily falling, but I did not know that these low cost DMMs are now selling at a hundred bucks a piece. I could now guess that sooner or later, the 9V energizer battery you will need to power these stuffs will cost more than the DMM itself.

Not too long ago, I also bought one cheap DMM from Raon. At that time, they are priced at something like 300 pesos each, much cheaper than the already low cost Taiwan DMM models. I bought one, not for the want of it, but to satisfy my tickled curiosity. Somehow, I sensed that this unbelievable low price has to have some catch in it, and this one I would like to test to find out.

I can no longer remember if my DMM got the same model number as your DT-830B. Neither could I say if it came from the same manufacturer, as these cheap DMM usually do not carry the tag of their respective manufacturers (this already tells me something).

I checked my cheap DMM calibration using a Keithley Model 2430 SourceMeter. This is not a calibrator instrument, but is just as good – it was a just recently calibrated source that has a reassuring rock stable output down to the last 6th (least significant) digit.

On test, it instantly revealed my DMM calibration is anything but good. But it is not the initial calibration that really scared me, it is the repeatability. This 3-1/2 digit DMM could not decide what to show on its two least significant digits, they just keep changing. It has the precision of a 1-1/2 digit DMM! After it flunked this initial yet very important qualification, I find it pointless to proceed any further.

To be fair, be aware that these ‘test results’ may not necessarily apply to your DT-803B. Maybe, and I do hope, these newer and cheaper models now do better than the one I had. But I felt less hopeful when you yourself had noted that this DT-803B DMM is practically useless when measuring low resistance.

Now think about this, this basic but very important diagnostics tool will be your eye and ear whenever you poke at your circuits. Would you use one that you know could be lying to you? They may be cheap, but are they worth the money?

Cheers!