Franc,

"With respect, voltage measurement is a very basic task. If you have to
ask this question, then you shouldn't be working on this device. There
are lethal AC voltages inside."

Agree, which is why I have not plugged in this LED Lite to AC.

Had hoped I could do the measurements without plugging it in!

"Examine the markings on the zener." What am I looking for? From your looking at the photos I sent what are the possible variations?

Thanks again for your detailed explanations and help!

Ken