I have used (and still use) in 50 Hz a ss amp, ss preamp, cd player, tube amp and tube preamp designed for 60Hz and never had an issue. Don't know if a tube tester would be any different, but for me it was a non issue.
Hertz 60 to 50 Question ??
I recently bought a tube tester. It is a 110-volt 60 Hertz model. I live overseas and am planning to use it with a step-down transformer from 220 input to 110 output. Nevertheless, since the electricity runs at 50 Hertz where I live this could cause problems. Does anyone have experience with using audio or other equipment rated at 60 Hertz in electrical systems that run at 50 Hertz?