My dad was a TV guy in the 60s, and had a tube tester. I learned to use it when I was about 6....which may explain some of my affection for tubes even now.
I miss those days. Life was simpler, for sure.
Nice extra free service at my local A/V store.
My local store Audio Video Therapy just added fully rebuilt floor standing Mercury Tube tester at their entrance. If you're old enough to remember it was the tube tester you'd find at many Drug Stores. You can go in and test your tubes free of charge. Nice addition.