Well, I can only go off what my father used to do. Open up the stereo or television and look at the tubes with a flashlight. Cussing a lot. Take a tube or two to Lucky's and test them on a machine located inside the store. If the tube doesn't light up he opened the case and pulled the tube he needed. Then he went home and with a flashlight, and cussing, installed the culprit. If it worked he got all puffed up and we were ready for Twelve O'clock High or listening to The Monkees, rather me listening to The Monkees.

Nice video; wish I had had that when I started teaching electronics 40 years ago...lol. It might have come in handy.

But actually; all of us Audio Research fans KNOW how tubes work...very, very well indeed!

I still don't understand how vacuum tubes can work since sound doesn't traverse a vacuum. Seems obvious to me.

Great vid's, nc. Like Lamont I used to go with my dad to Hiram's (precursor of Lucky's) or Sav-On or Thrifty's or S.S. Kresge (forerunner of K-Mart) with a brown bag full of suspect tubes and look for replacements. He was an optics tech with the Nortronics division of Northrop in Hawthorne, CA so he knew his way around a circuit. Made his own phenolic adjustment tools so he could tweak around the back of the set w/out fear of shock. Great memories, guys. Thanks.

Sound doesn't "traverse" a transistor, either; electrons do.

Same thing in a vacuum tube....

Quote:
Sound doesn't "traverse" a transistor, either; electrons do.

Same thing in a vacuum tube....

Yea, but at least a transistor has a physical connection unlike a device with nothing at all in it.
But now that I think about it, music must be able to traverse a vacuum, other wise I couldn't hear.