Questions tagged [crt-monitor]
Cathode Ray Tube monitors: principles of operation and use with computing devices. DO NOT REPAIR CRTs; SEE TAG WIKI FOR DETAILS.
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Why did 80x25 become the text monitor standard?
Prior to the 1981 release of the IBM PC, the VT05 (72x20 1970), VT50 (80x12 1974), VT52 (80x24 1975), and VT100 (80x24 1978) text terminals were used on many Unix machines and the PDP-11 (probably the ...
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Why were animated screensavers used instead of a black screen on CRT monitors?
Before the advent of modern monitors, CRT technology was used, which was vulnerable to screen burn-ins. Screensavers avoided these problems by producing animations instead of persistent images.
Were ...
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Why did some video games apparently use "interlaced" video modes?
I was under the impression that "interlaced" video modes was only a thing for remote television content because it saved bandwidth to only send 50% of the data to the homes, so you could fit ...
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Can the wrong sync frequency really destroy a CRT monitor?
I've read in various places that an incorrect signal of the wrong refresh rate can cause physical damage to a CRT monitor, but I've never found an adequate explanation of why this is so. Is this true? ...
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Adjusting focus for old CRT monitors
I have an old Atari SC1224 CRT which has badly lost focus over the years.
After taking the cover off, I can see various focus controls that can be adjusted by screwdriver.
Question: is there a ...
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What monitor did Atari recommend for its 8 bit product line?
I am curious what Atari recommended to users as an appropriate monitor for their 8 bit computers (400/800/800xl/etc).
For example, my Commodore 64 pairs nicely with a Commodore manufactured 1702 or ...
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Was the picture area of a CRT a parallelogram (instead of a true rectangle)?
This may seem like an absurd question at first, but I've been giving it some thought and I'm genuinely curious about the design details of these devices.
I was reading an answer on an unrelated Stack ...
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Computers with integrated monitor (all-in-one form factor)
The Commodore PET had an all-in-one form factor where the monitor was fused into the rest of the computer, making a single unit, not dissimilar to some early terminals like the VT100. This is ...
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What is the difference between the Commodore 1701 and the 1702?
Among the monitors offered by Commodore were the 1701 and the 1702, which, to my recollection, looked pretty much identical. Were there any cosmetic, functional, or other differences between the two?
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Did any computer allow overscan on a CRT monitor?
The issue doesn't arise on today's LCD screens, but on a CRT screen, because the edges are slightly curved, and you might not be able to be sure exactly how the individual screen is tweaked, it's not ...
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Did Apple bundle a specific monitor with the Apple II+ for schools?
Sometime in 1980 (or maybe 1981) my school district purchased its first batch of Apple II+ computers. I remember vividly they had absolutely no idea what to do with them, and so the machines were ...
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Which font with slashed zero is being used in this screengrab?
Do you know which font is being used in the video here: https://www.youtube.com/watch?v=xnudvJbAgI0? A screengrab of the video that shows a lot of text:
We can see that the zeros are slashed, so it ...
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Square pixels and TV output
Another question about color computers in the days of CRT televisions!
There is a consensus that pixels should be square, and so they typically are on purpose-designed monitors. However, looking at a ...
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Interfacing with vintage Canon monitor
I bought a vintage Canon monitor off a friend which I'd like to interface with and use as a cool retro monitor.
The problem is that I can't find anything useful about this monitor after days of ...
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Why didn't early color TV sets accept RGB input?
Early PCs generated RF signal, and later Composite video or S-video, to use a TV set as monitor. Why didn't color TVs of those days expose a analog RGB interface for direct connection from VCR/PC or ...
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What is the correct name for the old green/amber-on-black monitors, and what are the best vintage models to look for used?
I'd like to buy an old green-on-black or amber-on-black computer monitor, but I'm not sure what to search for. Are they called "monochrome" monitors, or something else?
What I want is one ...
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What are principles of vector CRT display? Simplest way to drive CRTs? [closed]
I am into playing with TTL to build 1970s style minicomputers. Aside from talking to them via some serial (or parallel) I/O port to a terminal, I am wondering about display output. This here is about ...
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Why does my CRT whine?
My Amstrad CTM644 CRT 'monitor' (really a TV grade tube with RGB inputs), makes a high pitched whine when powered on, audible to my children and cats, though no longer to my own ears. My research ...
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Physical resolution and control of old VGA (color) CRT monitors
I've just realized I have a gap in my understanding of the VGA CRT monitors of the 80386 era (1980s-1990s).
What was the phosphor resolution? It turns out I did not have proper understanding of the ...
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What causes the monitor to reduce to four lines on BK 0010 Focal?
When working with the Focal cartridge inserted on my BK 0010, the area displayed on the monitor suddenly reduces to just four lines
, instead of the usual 20
Each time this has happened when I've ...
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Monochrome CRT Repair - Horizontal offset
My CRT all of a sudden is shifted to the right. I cannot adjust it via the adjustment potentiometers, nothing changes when these are turned. If I increase the brightness, the whole screen turns green (...
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Did all integrated Commodore PET monitors always use 60 Hz refresh?
All models of the Commodore PET line had built-in monitors, and at least the U.S. models had 60 Hz refresh. For the European models there was no need for compatibility with European television ...
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Is it possible to swap the Apple IIc's monochrome CRT tube for a color one?
I just love the Snow White industrial design language of the Apple IIc, especially when paired with the Monitor IIc. It is a classic design that doesn't show its age. I've even recently seen them ...
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What were other colors beside green and amber for monochrome monitors?
In a movie that unfortunately I don't remember the name of, a monochrome monitor using red shade was visible. I found that quite fascinating back then !
Beside green, amber and apparently gray, were ...
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Why was the Microvitec Cub monitor made of metal?
In British schools in the early eighties, the iconic microcomputer was the BBC Micro, typically connected to the equally iconic Microvitec Cub color monitor, as described in this video.
Why this ...
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Is a normal B&W TV good enough for 80-column text?
S-100 bus machines normally had displays that had 64-chars-per-line. The VDM-1 used a 7x9 format, and I think most cards used that, so that would be 448 pixels. I understand that an NTSC television ...
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Price of early color monitor versus TV
Some computers in the seventies and eighties had the option of output to either a TV or a dedicated monitor. Suppose repurposing an existing TV isn't an option and you are going to be buying a screen ...
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Can I use my IBM P/N 93F0502 (circa 1992) monitor in a dual monitor setup with my modern Mac Mini or Thinkpad?
I have an old IBM monitor here and I'd like to use it as a second screen to my computer (Mac mini running Fedora or Thinkpad running Archlinux).
I plugged it into the electricity socket without a ...
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How to tell if glue or electrolyte leak from old capacitors?
I recently acquired an IBM 5154 EGA monitor that works pretty well. The only minor problem is that the screen is slightly off-center. I decided to take it apart to adjust it, but discovered that many ...
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Choosing a monochrome color at the monitor?
A monochrome monitor displays only one foreground color and one background color. Usually the monitor was manufactured to produce only one color, which was cheaper (both CRT and electronics) than a ...
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Safely adjusting CRT while it's on?
I have an old IBM 5154 monitor that works pretty well. It only has two issues: the screen is off-center and the color is too blue. I found a service manual for it that describes how to fix both of ...
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Why did CGA RGBI output leave DAC to the monitor?
CGA on the original IBM PC produced sixteen colors, one bit each for red, green, blue and overall intensity modifier.
The preferred output device was the later-arriving 5153 color monitor, which ...
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Connectors for green screen versus color monitors
Consider a pair of early 14" CRT monitors, one green screen 80x25 text, one color 640x480 graphics. It seems reasonable to conjecture that both could have the same resolution; at least if you suppose ...
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Sending video to Telerate 9" Green Monitor [closed]
I found an old Telerate green monitor at a thrift store and figured I could run my computer output through an HDMI -> AV converter with no problem, or a Raspberry Pi composite output signal. Turns ...
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What's the difference between an IBM 5153 (CGA) CRT picture tube and a color TV picture tube?
The IBM 5153 Personal Computer Color Display was a monitor designed to accompany the original IBM PC (albeit released a couple of years later) and provide a color display at sharp enough resolution ...
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Does the Atari 1040 STE work with the Atari SM124 monitor?
I have an Atari 1040STE. I'd like to use it with the Atari SM124 B/W monitor but I'm not sure it will work. It's my understanding that the Atari SM124 works fine with earlier Atari ST models, but when ...
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Monitor for an SGI Octane?
I just found myself being the sudden and proud owner of two wonderful Silicon Graphics machines, an Octane and an Octane 2, both in quite good condition (in particular with very few scratches to the ...
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What was this Apple external CRT monitor that looked like an iMac G3?
In high school I rescued an Apple external monitor from the garbage which looked like an iMac G3, only twice as big. It was blue but I bet it came in different colors as well. It might still be in ...
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Ideal resolution for color computer on PAL/SECAM
Suppose you were, in the early eighties, designing a color computer to run on an PAL TV with a free hand to choose the specifications within the limits of the technology of the time. What would be the ...
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Could monochrome systems produce better output for monitors than TV sets?
Many classic computers could optionally use a TV set as the display. At least in the early (pre-SCART) days, the TV would typically only have RF input, but if you were using a monitor, you could get a ...
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Retro emulation with perfect V-sync
I'm building an retro emulator to connect to a PAL (720x576i @ 50 Hz) CRT TV, and would like a perfect V-blank image, so the visuals are identical to original arcades and retro computers.
In other ...
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How to connect an HX-20 to a monitor via the RS232 port?
Using & Programming the Epson HX-20 Portable Computer by Eric Balkan has a tantalising passage on p. 172*:
T.L. Ronson of the HX-20 User's Group also notes that a monochrome monitor can be ...
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Can the 80-column display really be improved on a C128 and 1902A monitor?
The March 1988 issue of RUN contains the following tip from a reader on page 20:
Attention: C-128/1902A Owners!
If you use a Commodore 1902A video monitor with your C-128, here's a way to get a ...
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What monitor could render APL2 characters in 1985?
BACKGROUND:
In 1985, I took an evening class in APL at the local IBM as part of a high school Explorer Post (which was really cool, these guys giving up their time to teach us programming). Other ...
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Were there any square monitors other than PLATO?
The PLATO multiuser interactive computer system used – and indeed invented for this purpose – a plasma display, whose key selling point in the late sixties was that it did not need refresh, therefore ...
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Were vertical monitor arcade games programmed differently from those with horizontal monitors?
Many classic arcade games like Pac Man (Namco 1980), Assault (Namco 1988), Mercs (Capcom 1990), etc, use a monitor oriented vertically. I assume that they used the same physical hardware, with the ...
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Performance characteristics of the DEC Type 30 graphical display
The DEC Type 30 was an early vector graphics display, that was used for an astonishingly wide range of applications for the 1960s. It used a 16-inch circular CRT with high persistence phosphor ...
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Why not SCART for early color monitors
By the early eighties, it was starting to be considered desirable for computers to have color monitors. Home computers often made do with a TV set and accepted the consequent low resolution, but ...
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Sony PVM Connections / Composite Signale
I am trying to learn more about different video formats. I have a SONY PVM9044QM and want to understand the different connection options.
So I understand, that Y/C equals S-Video input.
But what does ...
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Digital to analog in an old 35mm film recorder [closed]
I'm looking at an old film recorder from 1985, the Polaroid Freeze Frame, the back of the machine pictured here:
From here: https://www.radiomuseum.org/r/polaroidco_freezeframe_video_recorder.html
I ...
