Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

Questions tagged [crt]

Anything related to Cathodic Ray Tubes (CRTs), i.e. specially built electronic vacuum tubes where an electron beam is focused and deflected on a phosphor-coated surface in order to display an image.

Anything related to Cathodic Ray Tubes (CRTs), i.e. specially built electronic vacuum tubes where an electron beam is focused and deflected on a phosphor-coated surface in order to display an image. Until about year 2000 CRTs were the electronic component used as screen in most TV sets and computer monitors, nowadays they are largely superseded by other technologies.

See also Wikipedia on CRTs.

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Why do CRTs have 3 electron guns?

I have been wondering about this for a while: Since the phosphor will remain excited for a certain period of time, I could imagine a single electron gun could target the red, green and blue phosphors sequentially instead having 3 parallel…
Thomas
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Why wasn't interlaced CRT scanning done back and forth?

I was studying the scanning of old CRT screens and the interlacing strategy for video, and I started wondering something. The raster scan process went top to bottom on odd lines, then back to top to raster the even lines. There is therefore a…
Stefano Borini
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Espionage by CRT mirroring

Quite a few decades ago (either late 70's or early 80's), I vaguely remember seeing on TV a demonstration of, what would now be called, mirroring of a CRT screen, that was over 30 meters away, without the use of any cables, fibre optics, wires or…
Greenonline
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CRT monitor SMART protection capability

In this wiki page:http://en.wikipedia.org/wiki/Framebuffer There is something called "SMART" protection capability to avoid monitor to driven it's hardware capabilities. An unfortunate side-effect of this method was that the display device could…
Standard Sandun
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How did analog color televisions "fix" alignment problems in three-gun systems?

I recall my grandfather panicking when I attempted to adjust the tint on his TV. He said that he would have to call the TV people to come and re-align it. I thought he was crazy at the time, but later learned this was a very real problem in early…
Maury Markowitz
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Components of a CRT whine

I noticed something as a kid with my Atari 2600 (and better ears). We can hear the 15khz horizontal freq but I noticed that the whine changes slightly (while the line frequency doesn’t) based on the background that was drawn. It was very clear with…
Thomas
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Melted CRT anode cap

I'm sorry it may not be the right place to post this but i'm not familiar with CRTs and old electronics so... here's my question: This crt made a loud noise so i opened it and found this when i tried to discharge it, and it seems that the anode has…
iMohaned
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An overview of the inside circuit of a CRT

I want to know how the inside circuit of a CRT looks, from what I've understood it is that you heat the cathode, then some of the cathode electrons are released, then it gets focused and accelerated using the anode, and finally it hits the…
Abdo Ismail
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Thermionic cathode heater filament conundrum

An old CRT I have specifies 6.3 V (DC, I believe) on the heater filament, resulting in a 0.6 A filament current (spec). But I measure the filament resistance as 1.8 Ohm. At V = 6.3 V that would result in a 3.5 A filament current, about 6 times too…
Gert
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CRT automatic focusing?

Has anyone ever heard of a circuit to automatically adjust the focusing anode on an electrostatically deflected CRT? Is there any way to even detect optimum focus other than by looking at the tube readout? I know on old CROs theres just a focus…
CrafterOfWorlds
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Where is Anode Cap connected in CRT?

On the expanding area of glass? Is inside of expanding area metal?
ssa2
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My CRT Television had blue patches when turned ON?

My CRT Television had blue patches on screen when turned ON, what could be possible reason? After moving speaker magnet(BIG) around the screen, it was possible to pull the blue patches from everywhere, and push it a corner of screen? How was this…
Amruth A
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Is safe to work with a CRT viewfinder?

While searching, I found CRTs that run at 5V-12V. These CRTs can run with very low power but is it risky to touch them? You can power these CRTs with 9V batteries but if you lick 9V batteries it doesn't kill you. Even running with Arduino:…
IWantJustBasicCollisions
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