How Cathode Ray Tubes Work. [video]

Great video. Seeing what it looks like inside with the phosphor and the mask was so enlightening. I also recently watched the one by Technology Connections, which was quite good: https://www.youtube.com/watch?v=l4UgZBs7ZGo

I feel like I have a much better basic understanding of CRTs now. They felt like utter magic before. Now it just feels a bit like magic. The only thing that still confuses me is how the electron gun itself actually works. I don't really get how electrons are being shot at all and why we can shoot them in a beam.

Great video and explanation, but he still doesn’t really explain how the magnets in the monochrome CRTs actually draw the image. How do they know where to point? How does it move so fast?

In the old days, our cars were powered by gasoline and every house had a ~25KeV particle accelerator in the living room.

There's an old site with a nice run down of building simple DIY CRT's using a glow discharge electron gun and laboratory flasks: http://www.sparkbangbuzz.com/crt/crt6.htm The glow discharge stuff is very easy to build as you dont need a filament/heater and power supply, it's a cold cathode gun. I wound up coming across another simple and fun project that demonstrates a very simple glow discharge gun in a glass bottle: https://hackaday.com/2011/08/30/diy-electron-accelerator/

I built one of those bottle accelerators but with some mods using a smaller Stuart's soda bottle. Cathode is a 0.5 in diameter Al spacer bushing mounted to one end of a 0.25 inch aluminum tube punched through a rubber stopper and the other to a tube adapter screwed to a KF25 vac flange. I then rigged up a stand to hold a vacuum manifold connected to my Alcatel 2008 vac pump and could pull a nice vacuum down to 0.4 Pa. The bottle gun's anode is a loop of 12 AWG copper wire inserted into a drilled hole and sealed with Faraday wax (safe and easy to make but messy and does not easily clean up.) Finally, wired it to my 200W Bertan +10kV 20mA supply. The +10kV lets me setup the gun as a common cathode putting the electron gun parts at ground potential. Only the anode is at high potential. I then decided to see if I could focus the beam and MacGyverd a lens out of a big 2 inch conduit bushing I had lying around in the electrics bin. Wound a bunch of 20 AWG magnet wire around it and found that building a big enough field to focus and sat it around the bottle neck. That big hunk of steel took a crap ton more power than I thought - I could focus the beam to midway of the bottle at around 300W (30V DC @ 10A)into the focus lens (yes it got very hot)! At full beam power I can melt holes in tin foil sheet using a focused beam.

Nothing makes me feel older than seeing a youtube video trend about CRTs. This was part of my high school curriculum.

Trinitrons and workalikes were very good, but the shadow mask displays that this video focuses on to my memory didn't have the excellent contrast and black levels cited. I remember most of them looking pretty dull, and downright silvery if there was much light in the room.

When I was a kid we had a Trinitron. I used a magnet on it once and pretended not to know anything about it as my dad called the cable company. Apparently it was able to degauss itself because the color went back to normal eventually.

Be interesting if we kept developing this tech. Where would CRT's be now?