Hmmm.....more justification for Joe T's constant advice to get a simple scope for checking things? It would have likely picked up the differences that a digital meter possibly missed. All depends on the meter's specs and useful settings.
I also have an older fully analogue meter that has proven invaluable and dead accurate over the 35 years of well looked after use. And it doesn't use batteries!
Related aside.....has anyone else ever laughed at how progress has made things more complex? Instead of me having a car radio that gets the signal direct from a transmitter, I now have to have my phone on, using mobile internet to receive a favourite "radio station". The phone then uses bluetooth to connect to the car system that processes the signal from the phone and gets it to the speakers. 😖
That's such excellent progress, isn't it?!! In the overall scheme of things how much "total" energy is wasted by this method? The list is endless.