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One of the design points for the BBC Micro was that it should be usable by the BBC itself as a low-cost broadcast image generator and Teletext editing device. The BBC, of course, broadcast on the PAL standard. This probably influenced the choice of resolutions, which use nearly all of the "safely visible" area of a typical TV. The highest ...


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The question mentions “early PCs” that generated a TV-compatible RF signal and “the color TVs of those days”. This would be a period spanning from at around mid-to-late 1970s to mid-1980s. The computer systems in question would be microcomputers aimed at the home market. By the late 1970s, new TV sets were already transistor-based and IC-based designs. ...


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Conjecture: Cable material that could cleanly transfer three analog video signals, plus sync pulses and identification pins, over several feet was probably not a cheap, mass produced item at the time CGA was introduced. Mind that VGA uses a quite special cable stock (several simple wires and three 75 Ohm coaxial lines), and there was likely only a reason to ...


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Many TV designs up into the 1970s were so called live chassis designs, which used one leg of the mains input as a reference ground. This saved materials and weight - given some early color TVs used 200+ watts at 100% duty cycle, you would have needed a rather bulky and heavy transformer, given that PSMPS technology was not really mature for consumer devices ...


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TV manufacturers didn't have a single, obvious RGB connection standard to implement. Physically, there was SCART (with competing European and Japanese pinouts), RCA, DE-9, and various manufacturer-specific DIN plugs to choose from. Then you have the various electrical signals to send over them such as RGBS, RGsB, RGBHV, YPrPb, digital RGBI, etc. And VCRs ...


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I'll take PAL to mean the specific composite-video signal format for color TV, deliberately excluding higher-resolution versions like S-video with multiple signal lines (see Wikipedia). The vertical resolution is fixed by the signal timing of 625 interlaced scan lines, meaning that you can either use interlacing and get a maximum of 576 lines with a very ...


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If this is about connecting the color computer to television antenna input via an RF modulator, then the local TV system variant matters, as both the RF modulator for the computer and the RF demodulator in the TV are built to use a certain composite video signal bandwidth. For a 625-line 50 Hz field rate TV system, the maximum composite video signal ...


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What would be the ideal resolution? There is no "ideal" resolution. TV screens use "overscan", which means that the full TV image is occluded by a bezel. That doesn't matter for movies, but it does matter if you have text on the screen. So you need to choose a part of the image that would be inside the bezel of most TV models, because ...


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In the early 80s, cost of RAM for the framebuffer was the dominant factor, closely followed by RAM bandwidth. The difference in resolution between NTSC and PAL systems is minimal in comparison to these factors (note that despite the different number of lines per field and different field rate, each technology used a very similar line rate of ~64us per line, ...


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When colour television broadcasts began (1960s, in the UK; perhaps a little earlier in North America?) there weren't any local devices that customers might want to use. Broadcast TV was the only source of images that any home user could imagine. Adding extra circuitry to handle separated R, G, B and sync inputs (with appropriate protections against overload ...


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Early colour TVs predated VCRs and home computers by many years. Even if it did not cost much, adding an RGB input would still be a cost for something that no one would use. However, it would have been more complex and expensive than you might expect today.


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The PDP-1 Type 30 display, which is the 'canonical' display for the PDP-1, was a point-plotting display, not a vector display. It was a specific device, not a general-purpose oscilloscope. Link to manual. The price list gives it at $14,300 in 1964, though that's the Type 30, not the 30E. HOWEVER, this 1964 PDP-1 price list lists OSCILLOSCOPE DISPLAY TYPE 34 ...


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The PDP-1 actually used a CRT that was designed for radar (see e.g. the Wikipedia entry). But the whole electronics around the CRT needed to drive the CRT and interface it with the PDP-1 was custom built. And as such, it was nothing like the electronics needed in an oscilloscope. The same is true for later displays used in the PDP series. So the assumption ...


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Well, I give you the SYM-1, as it could display text output on a user-supplied oscilloscope. Ray was just too much of an engineer to let that pass :) (*1) Beside that somewhat off beat example, I'd say next to every analogue computer would work great with a user supplied oscar. In a more general notion, at a time when displays became a thing, a user supplied ...


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I have a Eizo 9050s monitor (similar in features to the one mentioned in This answer), which has a "color switch" in the front, with the settings "green/color/amber". In "green", the signal to the red and blue guns is completely shut off. In the "amber" position, the signal to the blue is shut off, and the one to the ...


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Yes, back in the day my family had an IDEK brand color CRT that supported setting the color of monochrome signal. It was not a standard PC monitor for VGA only, as it supported both analog and digital inputs, and went down to 15 kHz as it was used with an Amiga as well. In the front panel there were three buttons for disabling each component of RGB ...


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I suppose it wasn’t that long ago when mono LCD panels were available, certainly by the late ‘80s and you could pick your preferred backlight. I don’t remember a monitor that offered that though.


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A form of this was used extensively for avionics displays. Known as the penetron (stop giggling), the CRT used a single gun and dual phosphor coatings (red and green). Each frame was drawn in two passes. In the first, low intensity scan the inner phosphor layer would be stimulated (generating, say, red light); a second scan at high beam intensity would ...


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I would look for a Goldstar Monochrome CRT monitor with VGA input. They made their name in Korean electronics in the early 90's and eventually became LG.


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Besides the other options mentioned, you might also consider a Philips 8833-series monitor, which were used a lot together with Amiga computers in the past. These are color monitors, but have a "green" switch. Maybe not quite what you are looking for (in the "green mode" it will still be, er, greenscale, not "true" monochrome), ...


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What are you probably referring to, was known as "Hercules graphics card" for IBM PC (XT,AT) compatible computers. Or more often "Hercules compatible graphics card". These cards were driving monochrome ("Hercules compatible") monitors, which were monochrome monitors with DE-9 connectors and 5V (TTL signal level). To recreate the ...


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Back in ancient times, we mainframe type people were given a "terminal", aka "CRT" (for Cathode Ray Tubes), or more simply, just "tube". They were IBM 3278 (green) and/or 3279 (four color) models, and loads of compatibles. The "real" ones from IBM weighed about 12 metric shit-tons. And yes, their characters were ...


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My favorites (back in the day) were DEC's VT-100 and VT-220 lines. I also had good luck with Wyse terminals (the Wyse-60 terminal actually had a calculator app built in). The Lear-Siegler ADM-3a models were pretty horrible, I think every one we had in the computer labs in college had had its speaker gouged out or stuffed full of gum. Datamedia DT-80s were VT-...


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A "monochrome" screen refers to any display which only displays one colour, based on the type of phosphor used. The type you are after is more specifically called a "green screen" monitor. Unfortunately an internet search for this term is going to produce a lot of stuff about movie green-screens - perhaps searching for "green screen ...


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What you are describing is a cathode ray tube (CRT) that could be part of a terminal such as a VT220 or an ADM5, but it could also be a standalone monitor. Early (80s) home computers would typically connect to a television (either mono or colour), some machines like the PET and IBM System/23 had a built-in CRT and others again used a standalone monitor. ...


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They were generally called "computer terminals" rather than "monitors". They came with a keyboard, character ROMs, interface devices, etc. The VT220 came in white, green, or amber phosphors.


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Are they called "monochrome" monitors, or something else? Yes. Monochrome covers all that paint in Amber, Green, Blue or white on black. What I want is one of those with glowing green letters made of thin lines on a solid black screen. That sounds more as if you're looking for a vector display. Something incompatible with most old hardware and ...


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