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14

This might just be stating the obvious, but Type 30 manual linked in the question describes the device as a random-position point-plotting cathode ray tube. Nowhere does the manual suggest it's a vector graphics display. It then further describes how the computer supplies the X,Y coordinates of a single point to be plotted. There is no facility to plot a ...


12

In that era you couldn't afford to build the raster displays that we have now. The RAM for the frame buffer would have been far too expensive. Vector displays were common, even though they had disadvantages - at engineering time you had to make a fixed-for-all-time choice between how long of a vector you could write vs. the persistence time of the phosphor....


10

Vector and raster graphics pose different challenges. Raster displays require the ability to very quickly generate a stream of pixels at a continuous rate. Unless one is willing to place severe limits on the number of objects per horizontal line and use separate circuitry for each such object (something many early video game systems in fact did) this will ...


7

The description of the Spacewar game gives some clues that the Type 30 was not able to display lines, but instead dots. Towards the end of the description, there is the listing how the spaceships were rendered, and even linear sections were given as repeated individual dots. With a true line-rendering capability, the engineers had surely used that instead of ...


7

This is really lots of questions, so a very general answer: If you want to know how retro vector displays worked, have a look e.g. at the Tektronix 4010, the Vector General, or the various vector displays for the PDP models. Bitsavers has manuals. The interface for all of these is a variation of the following principle: Store a "current position" as a ...


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 ...


5

Just what was it used for? The answer is in the name - to display graphics It doesn't make much sense to produce a list of application, but lets look at the core issue of having a screen at all: There were no of-the-shelf graphic terminals - or (CRT-based) terminals - at all. A terminal was a card punch, a tape punch (and their counterparts) or a typing ...


5

NOTE: This actually refers to the type 340, not the type 30, so it may be irrelevant! The Type 30 input commands worked in several different "modes", including point mode, vector mode, and character mode (with an optional character generator). The actual display was always point-based, unlike the Tektronix 4011/4014 displays which drew straight ...


4

Expanding the existing answer by temlib is that most osciliscopes have some form of X/Y input and better ones support Z (intensity) This allows you to sidestep the complex signal drive problem to the CRT coils and just wrangle the primitives to DAC output part of the problem. And you'll need a decent scope for poking the back of a CRT anyway. Once you have ...


4

This gives me the idea of driving a CRT tube raw and naked right from the computer board (set). Perhaps all the high voltage stuff stays inside the monitor housing, but everything else would come from the display module in the computer, i.e., horizontal and vertical deflection and the intensities of the electron rays, monochrome or RGB. This would ...


4

You can drive a vector display with a few DACs driven by a FPGA for timing and sequencing the patterns. For a cheap implementation, you can look at the old Vectrex game console which is well documented. It uses only one 8 bits DAC, one analog multiplexer and a few op-amps. Lines are drawn by setting charge current to a R-C circuit, the CPU doesn't ...


3

The PDP-1 was priced to be sold to a lab and was relatively easy to interface to. This means that it could be used for processing and displaying data from a variety of equipment such as mass spectrometers and so on. It was also used by ITEK for one of the very early CAD systems in 1964, the Electronic Drafting Machine (PDF warning). It could also be used as ...


1

There was two main ways of doing this, exemplified by a storage display as used in the Tektronix 401x and the VS-11 type displays used by Digital. The 401x was an ASCII driven terminal and contained its own processors. Normal text was written in a dot matrix font at several prefixed scales, not as vectored glyphs by a pseudo rasterizing mechanism. Graphics ...


1

Another issue here: The main value of vector displays is they allow for a higher resolution than raster technology--but these days raster has gotten good enough that this is basically a non-issue. There are two downsides to vector systems that haven't been mentioned so far: 1) Vectors draw lines. The only way to fill an area is to scribble back and ...


1

The PDP-1 was designed as an unofficial successor to the MIT Lincoln Labs TX-0, which also had a similar display. On the TX-0 this had been used for interactive debugging as well as graphical display of the results of experiments (eg an early machine learning experiment that simulated the way a mouse learns to navigate a maze); it is likely that these ...


1

Trammell Hudson's V.st implements a USB to vector display driver using a Teensy 3.2 and some DACs. It looks like there are only available as single boards to build yourself.


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