I agree, but suggest not a digital meter, or at least use one that measures RMS; You may be dealing with odd waveforms.
Also, I think under no load condition many electronic transformers will shut down and show no output.
(Are you sure they are 20 watt lamps ?)
Yep they are 20 watts, and you are correct the electronic transformer shows 0 volts on my digital meter. Should I try my old analog meter?
