One of the pleasures of my childhood was when the TV set would stop working and my father and my uncle would fix it, right there in our living room. Which meant they had to take it apart first.
I didn’t know this at the time, but my uncle was an inventor with lots of patents to his name. He worked for RCA, on the cutting edge of electronics. As for my father, there was no appliance in his home that he couldn’t take apart and put back together so it worked; and he could explain how everything worked, too. By contrast, I live among all kinds of hi-tech stuff without a clue as to how any of it works. It might as well be magic.
So my father and my uncle would take the TV apart, and its innards–mostly vacuum tubes, which I found endlessly fascinating, and it looked like there were hundreds of them–they would carefully spread out on the floor. Somehow they isolated the tubes that were probably at fault, and took them to the local hardware store to be tested on a tube-tester like the one pictured above. I loved that! It was even cooler than the machine that used to shake cans of paint. My daddy liked to take his kids along wherever he went, and I was always up for a trip to the hardware store.
Having learned which tubes needed to be replaced, they would buy them, come back home, and put the TV back together–and voila! Good as new.
I would give an awful lot to be able to watch them do that again.