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Old 05-18-2018, 08:47 PM
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dyetalon dyetalon is offline
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Join Date: Nov 2007
Posts: 134
Hi guys

Ok it took me a while to find my CRT images. That was back in 2006.
My wife and I went nuts for a while playing with magnets on a Sony Trinitron.
I even modified it by adding resistors to ground off the grids, so it just emitted electrons from the cathodes.
No video to deal with, just pure electrons being boiled off the old fashioned way.

Anyway, I'll post the images with a little explanation, and you guys figure it out.

But first, let me make it clear that there is a difference between shadow mask CRT's and aperture mask CRT's.

When color TV's first came out they combined the RGB by guiding each color so they converged on little holes in a piece of metal behind the phosphorus screen. They were difficult to align (RCA had a panel with over 20 adjustments) and if you even moved the TV to another location, you had to 're-converge' the TV using all of those crazy adjustments. These were 'shadow masks' CRT's.

The aperture grill was perfected by Sony, who's TV's and monitors were the best video available back in the days. Their method brought the dot pitch (same rating we use today) down to .2mm which was pretty darn small back then.

If you used a magnifying glass and looked closely at the shadow mask screen while it was running, you would see the image on the left of pix1.
If you took a magnifying glass to one of the Trinitron screens you would the image on the right of pix1.

So instead of a sh*t-load of particle chains making slits, we have a metal screen with a bunch of slits. Do you notice the bands of light on the Trinitron seem to be continuous and not looking like little slits?

Ok here's a couple more pix. 3 & 4

3 is a magnet on a shadow mask CRT and 4 is a magnet on a aperture grill (from my modified Sony).

Do you see the correlation I'm trying to make?

I'll be back...
Attached Images
File Type: jpg pix1.jpg (263.5 KB, 13 views)
File Type: jpg pix3.jpg (144.6 KB, 10 views)
File Type: jpg pix4.jpg (179.4 KB, 13 views)

Last edited by dyetalon; 05-18-2018 at 10:46 PM. Reason: clarity
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