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63

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 ...


21

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.


20

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 ...


14

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 ...


12

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 ...


11

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 ...


10

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 ...


8

Somehow this answer is self answering, isn't it? If there are systems offering more than 80 columns, why should any developer writing for this platform ignore them? Just take a look at PCW applications, starting with this very basic manager form: Any usage is always about context - here especially the context an application is used or targeted at. If one ...


6

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 ...


6

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 ...


6

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 ...


4

I got a 30 year old Grundig CRT television to work with an Amiga by connecting it via a SCART cable that came from a Profex monitor (which apparently used SCART as input) and turning on Teletext with transparent background (i.e. the option to read Teletext while watching TV in the background). Without turning Teletext on, the TV screen remained black. ...


3

Since it doesn’t look like the display is “squished” (with the entire display in that area) I suspect one of the two 41264-15 used for video RAM (UC6 or UC7) is at issue. It could just be a bad solder joint causing the IC to be unpowered, or it could be the IC has gone bad and needs replacement. It could also be one of the address lines or one of the ...


3

Other replies already give examples which use proportional text, so I won't add to them. However, I want to challenge the claim that "[s]ure, it would be a bit slower to render text, but for many purposes, surely worth it." To do it right (rather than cheating in a demo) is more than "a bit slower". Look at how text rendering is done with ...


2

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.


2

I would strongly recommend, if you're okay with tinkering, to just order one of the co0perdragon designs and install it internally. It's a raspberry pi 0 (not even W) powered board that you plug in between Denise video chip and your motherboard and it allows 12bit RGB video to be displayed through HDMI port on RPi. I have this done on all my Amigas from 500 ...


2

On the Soviet home computers of the series BK (BK-0010, BK-0011, BK-0011M, which were clones of LSI-11), the fonts could be loaded directly into memory, when using many operating systems, like ANDOS, MKDOS, AO-DOS. The OS shell had an option to save the current appearance for the next OS load. Below, an ANDOS file manager with a custom font enabled and a ...


1

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. ...


1

Character generation can actually be done by partially analog style circuitry- and this has been done, for example to generate the on screen numeric readouts on Tektronix 5000/5400/7000 series oscilloscopes. Basically, some analog constants are "switched in" for whatever glyph is desired, and gradually applied one after another to the coordinate ...


1

Sure, it would be a bit slower to render text, but for many purposes, surely worth it. Yet all the 8-bit programs I can find, still used a fixed width font. For some purposes it would be worth it, but many others it wouldn't. Ever seen ASCII art rendered in a proportional font? Using a fixed width font makes it much easier to get even spacing and line text ...


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