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How the IBM 1403 Printer Hammered Out 1,100 Lines Per Minute (ieee.org)

Posted by BeauHD on from the behind-the-scenes dept.

schwit1 quotes a report from IEEE Spectrum: The IBM 1460, which went on sale in 1963, was an upgrade of the 1401 [which was one of the first transistorized computers ever sold commercially]. Twice as fast, with a 6-microsecond cycle time, it came with a high-speed 1403 Model 3 line printer. The 1403 printer was incredibly fast. It had five identical sets of 48 embossed metal characters like the kind you'd find on a typewriter, all connected together on a horizontal chain loop that revolved at 5.2 meters per second behind the face of a continuous ream of paper. Between the paper and the character chain was a strip of ink tape, again just like a typewriter's. But rather than pressing the character to the paper through the ink tape, the 1403 did it backward, pressing the paper against the high-speed character chain through the ink tape with the aid of tiny hammers. Over the years, IBM came out with eight models of the 1403. Some versions had 132 hammers, one for each printable column, and each was individually actuated with an electromagnet. When a character on the character chain aligned with a column that was supposed to contain that character, the electromagnetic hammer for that column would actuate, pounding the paper through the ink tape and into the character in 11 microseconds. With all 132 hammers actuating and the chain blasting along, the 1403 was stupendously noisy [...] The Model 3, which replaced the character chain with slugs sliding in a track driven by gears, took just 55 milliseconds to print a single line. When printing a subset of characters, its speed rose from 1,100 lines per minute to 1,400 lines per minute.

10 of 174 comments (clear)

  1. I liked the dot-band technology by dwywit · · Score: 4, Interesting

    A blend of band printer speed, with dot-matrix flexibility. The print stream could include a change of fonts, so a title or chapter could print in large, bold font, and the body in regular serif font.

    --
    They sentenced me to twenty years of boredom
    1. Re:I liked the dot-band technology by Applehu+Akbar · · Score: 5, Interesting

      The 1403 was my first printer. Computers did not spend much time interpreting or summarizing data in those days, but focused on blazingly fast output to the endless stacks of greenbar paper the world ran on. People had to actually pore through those reams to find out what was going on. Even the developers had only hexadecimal printouts of main memory as a debugging tool. And you knew exactly what was in "core" too, because you had coded in Assembler.

    2. Re:I liked the dot-band technology by kolloid · · Score: 3, Interesting

      It was my first printer too. One of the first models of 1403 on a 1401. Around 1967. Before learning to program the machine I spent some time as operator. Our 1403 was not that fast. It printed 600 lpm with the "commercial" printchain, which only had upper case characters, numbers and a small number of special characters. There were fuller printchains, with lowercase letters and such which were also correspondingly slower because there were less repetitions of the character set along the chain, so a given character took more time to get to its hammer. The noisiest "scream" was when the machine printed a line of 132 hyphens, a very popular decoration on headings. A single hyphen would pass over all the hammers on the line, which fired one after the other producing a high frequency shriek. Not too merciful on your ears but one gets accustomed to anything...

  2. Fan-fold Fan by namgge · · Score: 4, Interesting

    What I miss about the demise of these beasts is the the essentially unlimited supply of fan-fold paper that could be used for everything from drawing really long diagrams that went round all four walls of the office to making paper hats for kids' birthday parties. It had to be very high quality to avoid getting shredded as it flew through the printer. They were indeed v. noisy but anyone in the same room as them went deaf so the problem was sorta self-limiting. C.

    1. Re:Fan-fold Fan by dwywit · · Score: 3, Interesting

      I also had the pleasure of running a 5225 shuttle-matrix printer. Fairly fast, and quite noisy. Some of the actuators needed replacing at some point and the IBM CSR told me some interesting facts about the drive motor - the only one I remember is that it was about 1/2 horsepower, and you'd break your wrist if you used your hand to stop it turning. He left a 'dead' actuator behind for me to play with - I put a car battery's 12VDC across its terminals and it got very hot very quickly - I suppose the duty cycle was a few milliseconds on, then many milliseconds off, and it was designed to cool during the 'off' period.

      --
      They sentenced me to twenty years of boredom
  3. this printout is from an IBM 1403 by ei4anb · · Score: 3, Interesting

    I found an old printout among some old maths books. Our school was close to the NUIG university engineering building and the professor had invited our maths class to learn how to program the IBM 1800 computer. This was one of my first programs. http://2eo.blogspot.ie/2014/04...

  4. video by fattmatt · · Score: 5, Interesting

    Here is a video of one in action ... built like a tank...

    https://www.youtube.com/watch?...

  5. line printer noise as music by Anonymous Coward · · Score: 2, Interesting

    well, not quite music, but when we printed checks, forms, or similar material -- where every page was identical in terms of where you needed to print something, then the cadence of the sound would tell us -- from way outside the computer room -- what specific print job was running.

    amazing stuff...

  6. Re:Testing, Testing by Alain+Williams · · Score: 5, Interesting

    I worked on ICL system 4 mainframes, we had a couple of these printers. A friend looked up the order of characters on the chain and printed a file with that on many lines. So all the hammers went forwards at once, then nothing, ... next line, all the hammers at once, ... He actually got the printer to rock forwards and back a little!

  7. Ah, the old line printers by fnj · · Score: 4, Interesting

    I remember my first post-university job in 1972 at Alpha Industries, a microwave house. They took me on to work with an HP 8542A automatic microwave network analyzer on which they invested a quarter of a million. It was 3-4 full height relay racks of equipment including the excellent HP 2100A mini, which had as I recall a full staggering 16K of magnetic core RAM, and an impressive set of peripherals including a 300 cps high speed optical paper tape reader, high speed paper tape punch, a huge heavy-duty ASR-35 TTY ... ... and ... a gigantic CDC 300 lpm rotary drum line printer built like a Sherman tank, the make and model I can't recall. It was cowled with sound absorbent structures, but when you raised the top of that baby to revel in watching it print, the deafening staccato noise was enough to put a boiler factory to shame. When it printed out a long line of dashes, there was a crash like the crack of doom as all the hammers came down at the same instant.

    Everything was on preventive maintenance with an HP specialist. As I remember it, the mini was phenomenally reliable, mostly just burned out indicator lights, but all the peripherals broke down all the time. We called the tape reader the "tape render", the tape punch the "tape pinch". Except for the ASR-35. It was night and day to the shitty light duty model 33 which the hoi polloi didn't know any better than to stick themselves with. That model 35 just soldiered on. Somebody broke the glass window once or twice leaning on it, and the type box shed a key once every few years (and the type box was swapped out in about 30 seconds), but other than that it was NEVER down.

    The microwave test equipment and the HPIB connecting it all was actually quite reliable.

    I had pretty much free reign in my own spacious air-conditioned room. I shared with an assistant production and development testing duties for the product line on the network analyzer, but the fun part was, I got to write customized test programs in FORTRAN and HP BASIC.