I remember in the 80s, devices would all come with the complete schematics right there in the box. I remember poring over them after buying something, I thought it was fascinating. Like my TV, computer etc. Everything.
This should really be brought back, even though component-level fixing is not nearly as easy as it was back then.
In the 1960s DIY TV repair was such a big thing that there were self-service kiosks in supermarkets that sold vacuum tubes and included a tube tester.
When your TV stopped working, you took the back panel off with the TV turned on and looked to see which tube was not glowing. You would then turn the TV off, pull that tube from its socket, take it down to the supermarket, stick it into the correct socket on the kiosk, and press the "test" button. A meter or lights on the kiosk would tell you if the tube was dead.
If it was, you looked up the tube in a book that was attached to the kiosk. The book would list the part number of an equivalent tube sold at the kiosk. You'd grab the right tube from the racks of tubes in the kiosk, go pay for it at the checkout stand, take it home, put it on the socket, and 99% of the time that fixed your TV.
If that didn't you might take the rest of the tubes in and test them just in case the problem was a tube failure other than a burned out filament.
Only if that didn't do it did you call the TV repair shop.
Wow, I would so not do that without rubber gloves or something. I've always been pretty hesitant working on CRTs knowing the voltages present in there (and they could linger for a long time due to charged capacitors).
Was the failure mode of tubes always such that it would stop glowing? I'm surprised they always failed in that way. I suppose the main issue would be that the heater filament would burn out and stop emitting electrons. Just like the filament in a light bulb.
When I was young tubes were already becoming uncommon. If a device still used them it was only for some high-power stuff like an amp final. Though of course the CRT itself lingered much longer.
Vacuum tubes have other failure modes besides the filament burning out, but the filament burning out was by far the most common.
A tube might have a filament life of many thousands of hours, but a TV might have a dozen or so tubes so the odds were highest for filament burnout when your TV suddenly stopped working.
I recently bought a cheap Chinese electric cooker just for fun. The instruction "manual" was a flimsy piece of paper. Yet it still contained schematics, as simple as it was.
This should really be brought back, even though component-level fixing is not nearly as easy as it was back then.