It's not the meter's fault - they are built in a way that will ALWAYS read DC voltage high, depending on the current. That's not a fault of the meter - it's a property of electrical power and the way mm's are made.
More expensive meters, measure true voltage, by adding more sophisticated and expensive circuitry. If you want true RMS voltage readouts, you'll have to get a more expensive mm with that feature.
For reading AC, etc., fairly accurately, you don't need the true RMS feature. The biggest problem with cheap dmm imo is their lag in settling on a final reading (which get's dang infuriating if you have a lot of tests to be made in a short amount of time), and their propensity to drop dead.
You select the wrong range, the wrong setting on the dial, they fall over on the bench when you're stretching out the leads to take a reading, etc. -- and Poof! They're gone to join their mm ancestors.
For my toolbox I use a real cheapo from Radio Shack - worked fine now for a dozen years- yes, it's entirely analog.
For electronics trouble shooting, testing electrical problems on cars or my truck (lots of DC obviously), it's time for the Fluke. It knows all about RMS for DC circuits, digital, quick, and protects itself well from every wrong turn of the dial I've made, so far (I don't make many).
A good dmm is not an expense if your work/study requires one - it's an investment. Get a good one, and treat it well. Oh, and learn about RMS DC voltage, of course.
Adak
.
