I can't believe... The very first steps in electronic for me and I must have a broken equipment!That's FRUSTRATING!!!
The good news is, it's rare!
Test equipment tends to be reliable. If it breaks, it's usually a broken test-lead or something, and it's usually more obvious, like the reading never changes, or it's just "dead".... Test equipment can
go "out of calibration", but it usually doesn't drift too far, and hobbyists rarely worry that kind of precision/accuracy. Your meter is not out of calibration. Its broken or defective...
When I chose the scale 200V at DC (!), FYI -
It's generally safe to use a lower scale, even if you don't know the voltage. i.e. The meter should not be damaged if you are on the 20V scale and you connect to 200V, or if you are reading Ohms and you accidently connect to 200V, etc. You should just get some sort of "overload" display.
The exception is current
. That's why there is usually a special connector on the meter for measuring current. Too much current, or "shorting" the current-probes across a voltage
-supply can blow the current-fuse in the meter, or it can damage the circuit you are measuring. (This has nothing to with your problem... With a
blown current-fuse, the meter will still measure voltage & resistance.)