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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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