My volt meter, ($25 Vellemann) persistently shows output DC voltages from transformers as TOO HIGH as compared with the nominal output voltage posted on the side of the various transformers. I have a whole box of 5, 9, 12, 14v transformers and they all show the same 50% (approx.) too high reading then expected. A 5v output shows 8v. A 12v might show 18v, etc. I use the transformers successfully on appliances and nothing blows up, so I'm assuming it's the voltmeter that's at fault. But when I use the same voltmeter on D, C, AA, AAA batteries the meter shows the expected voltages. Also I have a voltage regulator "chip" that outputs 5v and the volt meter shows 5 volts DC output exactly. So the misreading seems specific to transformers. Can anyone explain this? By the way, there are fresh batteries in the voltmeter.