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60

As so often with basic measurements like this, the roots have been laid out way before today's computers, even before computers (non human that is) at all. From what I read, most line printers have 132 columns. Also, the VT-220 and presumably other terminals may be switched between 80 columns (that's a usual width) and 132 columns. The number is a result ...


37

The paper I used in my dot-matrix printers (and still buy and use today) has 60g/m2 for the cheaper green-lined type and 70g/m2 for the pure white version. There is a rough guideline in the paper industry to calculate paper thickness from weight per square meter: t = 1.3 * wsqm / 1000 60g/m2 roughly ends up at 0.08mm, 70g/m2 around 0.09mm EDIT: Just ...


36

Fonts for text rendered to the screen or paper in a graphics mode would simply be data shipped with the application. If this was perceived to be non-copy-able, it is likely because it was not (obviously) in a standard font format, and perhaps intentionally obfuscated. It is also worth noting that VGA cards permitted relocating the text mode character ...


23

There is an old carboard box that used to contain fanfold paper right next to me. Using the label on the box for the number of sheets and a ruler to measure the box, a stack of 2200 sheets was 7 1/2 inches thick, which is near enough 300 sheets per inch. or 0.085mm per sheet if you prefer those units. This would have been plain white paper, the stuff we ...


16

they save every program from needing its own separate encyclopedic knowledge of every printer on the market. But then came PostScript, the theory behind which was that you would prepare a printable file in a standard format For one, Postscript isn't a standard format printable file, but a standard format document description. It may (and does) contain ...


15

DOS knows nothing about graphics fonts (mostly: it supports different display fonts which can be loaded using CHCP to change the display's code page, and some other minor details.) It was up to each program to come up with their own method of sending text and images to the printer, generally with the help of a printer driver that contained font metrics for ...


13

The United States has its own paper sizes, two of which are 11"x17" ('ledger/tabloid') and 8.5"x11" ('letter'), which are similar to A3 and A4 and have the same sort of predominance. Early fixed-width font printers usually offered a 12 characters-per-inch typeface. 12*11 = 132; so 132 characters is the number you can fit on a landscape 'letter' page, or a ...


12

Looks like inverse polarity. The CR code is 015, 00001101 in binary. The codes for "=" and "y" are 075 and 171, 00111101 and 01111001 respectively. Note the sequence of four zeros in CR, and sequences of four ones in "=" and "y". With the inverse polarity, the character boundaries will depend on the speed with which they are sent because the start and the ...


12

Speed Teletypes were not all limited to use over a modem. Many (e.g., the Model 43 - I had one of those) even had an RS232 compatible interface and could easily be used as a regular computer printer. But since most teletypes were designed for communications, and typical modems of the time were low speed, the teletypes themselves were low speed printers. ...


11

Cost There are significant licensing costs and equipment costs. I'm sure PostScript needs quite a bit more RAM & processing than some of the lower levels of PCL and similar printer languages. As I noted in my answer on trackballs and elsewhere, even a small increase in cost can have a big impact on sales and/or profitability, particularly at the low end ...


10

DOS itself did not manage them. Development environments used to ship with libraries that could support graphics modes, some with built-in font support. Some had vector fonts, some just blitted a dot matrix, favorably 8 pixels wide so one byte could encode one monochrome character scan line. The operating system contributed little to nothing. A popular ...


10

PostScript was quite demanding. In the early days a PostScript printer might well be the most powerful computer in the building, hence expensive. University students ran jobs on the printer to get done faster. In a world where price is important, this was most likely the primary reason. Look at the cheapest printers available and check if they run ...


8

I successfully got the RK-P400C printing from a serial console (minicom on Linux) today. Here's how to do it for future reference...;) The DB25 connector on the right side is a 25 pin serial port. At the top right of the typewriter there are sets of switches to select font and size, at the far right of those are two switches with the labels "KBI, KBII, EXT" ...


8

I used to have a Diablo 630 DWP saved from the dump. This did produce nice graphics using a dot character and micro spacing together with my AT compatible of that time. The whole procedure was, however, not very friendly to both ribbon and paper as you say, you had to reduce wheel impact (by retracting the solenoid) as much as possible to save both from ...


7

The teletype was not only the printer but for some old systems it was the only monitor for standard output. Having a CRT monitor made that function obsolete so that leaves only printing. The teletype was originally designed for copper line telephone network based text messaging. MS-DOS had no networking capabilities but you could install a modem in early ...


7

If the printer is offering an actual RS232 port, this should be identifiable by there being an RS232 level converter IC near the connector on its logic board: Usually, there will be a DS232/MAX232 or other MAX23x series IC, or a NEC D4711/UPD4711, or a combination of any of MC1488/MC1489/SN75188/SN75189/GD75189/GD75188/GD75232... This chip inverts the ...


7

The assumptions of this question are at best misleading and maybe based on personal experience, but not the situation at the time cited. As requested I just pulled out the very second issue of Kilobaud Magazin of February 1977 (*1). Right at the beginning there is an ad on page 12 selling ASR33 starting at USD 840. Page 54 shows an ad offering an Olivetti ...


6

Well, having a separate sound file will be a challenge. beside the fact, that you'll always get the way louder base level of a computer room with it, it also depends a lot on the type and model of line printer. Equally important, the sound isn't much impressive as long as the cover is closed - yes, it did make a huge difference. Maybe try this video The IBM ...


6

I don't know if this is the "best" solution, but I have found applying Singer light sewing machine oil to a dried-out fabric printer ribbon appears to be effective. This oil is odorless. Amazon: https://www.amazon.com/dp/B000YZ1Y06 Apply sparingly a drop at a time, and then set the ribbon aside and allow it time to soak or it will make a mess on the paper ...


6

Fax machines used to use thermal paper by the pallet, and it is still commonly available wherever office supplies are sold (including amazon). While this will be wider (not, as the problem is with the cash register rolls, narrower) than what these vintage printers need, this problem can be fixed with a guide and a sharp knife (and in the worst case re-...


5

In the old days(tm) it was common to reink fabric ribbons for typewriters, in fact, the early ones where made that way. I kept using that practice during the 70s and 80s for daisy wheel and dot matrix printers. In theory ribbons could be reinked an unlimited time, but in reality wear on the fabric (too much movement due the hammer) limited this to like a ...


5

In the US, paper is normally measured in pounds (lbs.) with the actual measurement defined a little differently depending on the type of paper - "cover", "text", etc. That is a very long discussion, and not that relevant here, here is one sample chart comparing types of paper/weights. The end result is the usual way to refer to office paper, including, in ...


5

132 column printers were a defacto standard decades before it became common to print on sheet-fed A-size (8.5x11 inch) paper, let alone in sheet-fed in landscape orientation, so an explanation based on 12 CPI and 11-inch long paper in landscape orientation certain is not the origin of the 132-colum standard. For example, most models of the IBM type 1403 ...


5

Yes - when at school I wrote a program for the Amstrad PCW that would do this. It's available for download as DSHOWSEA.COM from http://www.seasip.info/Cpm/software/amstrad.html . The only test I ran was on my geography master's printer: a simple drawing of rectangles. With the dots at their closest spacing, it chewed up the paper rather.


4

Not a simulator as such, but the BBC has just released an archive of its sound effects library which contains a couple of "line printer" recordings. Explore http://bbcsfx.acropolis.org.uk/?q=printer Try the two tracks labeled "General computer room atmosphere with printer in foreground" - one on the first page of the list, the other on the second. To ...


4

4 3/8 inches is 111.125 mm. A Google search for the Swedish term termopapper (thermal paper) 110mm gives me at least four hits on the first page alone for online stores that sell such paper. While none of those four appear at a glance to state whether it's in stock or not, it's clearly possible to procure. They even appear to offer different core diameters, ...


4

Yet another factor that hasn't been mentioned is that ink jet printers have become far more common than laser printers, and have a critical ability that laser printers lack, which in turn propelled the use of PostScript: the ability to suspend and resume printing in the middle of a page. Normal printer drivers could print pages which were too complex to fit ...


3

Most of you guys sound like you've read a few things but weren't around at the time. Not a complaint, just an observation. I worked for General Electric Information Services [GEIS] (Div. of GE that sold mainframe time-sharing globally). In the late 70s through the 80s, we used Genicom TN-200 and TN-300 printing (dumb) terminals as text only printers via ...


3

While Leo's answer seems possible, I find a reverse polarity problem relatively improbable when standard off-the-shelf equipment is used. I wouldn't want to rule out Leo's answer completely, though, just point out a possible alternative (even if I would assume that with reverse polarity at least the number of characters sent and apparently received should be ...


3

In addition to manassehkatz's answer, the other reason for printer drivers is to reduce cost in the printer. A postscript interpreter requires significant computing resources, especially for complex documents. By doing that processing on the computer and then sending a simpler, easier to handle data stream to the printer you can leverage the greater power of ...


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