The sound it made was halfway between a hive of angry bees and a chainsaw.
They had one of those in college
The sound it made was halfway between a hive of angry bees and a chainsaw.
I had 2 in my office
I salvaged them from a dead mainframe shop. Added a SCSI board converter from the mainframe connection (black box catalog). Drove one from sco Unix mpx and used the other for parts.
Keep in mind I had to maintain this thing like a car, vacuum and clean it regularly, swap the bands when they failed, troubleshoot failed hammers, swap logic boards (it had a bunch of boards that controlled portions of the hammers), etc. I was so happy after about 2 years my boss gave me an assistant and my first act of delegation (in my life) was to hand off printer maintenance to him. He handled it like a pro and all was good. My pfy all grown up.
Seriously. Louis (his assumed name, his real name was unpronounceable to me) had a master's in comp sci but he ended up my assistant for 3 years. It was great for both of us. But once a month when the thousands and thousands of proofs needed to be printed overnight, he was pissed.
But all day before while he did the maintenance tasks and shined up that printer, it was like a race car mechanic getting ready. He was proud. That printer was something else.
Served me well for 6 years, then I left the job.
Edited by crazy March 9, 2021, 09:55:27 AM EST
Someone has to have video of it online
What would be good search terms?
That's the marketing brochure. I had the two printers on the first page, the slower one was my parts printer.
Edited by crazy March 10, 2021, 08:22:16 AM EST
Could be a different model, or the nature of what they're printing, but I remember a more continuous buzz sound. This one sounds more like a machine gun. Somewhat familiar though.
While looking, I found this, which is really cool and probably way more hazardous than it looks.
Seems that way but is not the same device
But it is very close. That's a hammer bank band printer. I can't imagine they sounded much different. The machine gun chugga chugga chugga that you are describing is very straightforward. Every single character got a hammer and those hammers had to smack that spinning band that had the characters and symbols. The characters and symbols would be more common letters would have more positions and less less positions. So there were many letter e and very few letters z.
I'm pretty sure the limiting fact was actually the centronics printer port. I miss remembered in my initial description concerning the scuzzy configuration. Later on devices in my life were bus and tag to scuzzy. But this particular one was a bus and tag ripped out and then centronics just popped in. centronics ain't that fast compared to how fast this thing could actually throw those characters on that page.
Oh and that video had that printer running open. We do not run it open. It is too damn loud and the actual printer case had sound dampening materials all throughout to absorb it. I truly shared my office with one of these things 3 ft away with the parts one another 10 ft away. We do not run them open, that hurts our ears.
Now the next video you showed was the bursting machine. When I worked for, never mind I'm not specifying yet again, we had many many of those. And every time I see that paper fly by I think about the danger of the possibility of the paper cuts. Paper going that fast can cut your goddamn fingers off. And the people running those machines don't usually speak English very well. So trying to transmit the level of danger does not often go well.
The one I remember was definitely run closed
I also remember it as a wider format. Maybe more hammers running, but more muted, would give a more continuous sound?
80 was the default and 132 was wide. Didn't get any wider. That meant we had 132 hammers.
I'm a bit confused when you talk about continuous sound. If you got s*** to print the sound will be continuous. The chugga chugga didn't scare me. It's when the chugga chugga paused and the form feed kicked in and it went to the next page. That could cut my hand off.
Also, because it could go through so many boxes of paper so fast the little dots from the drilled paper would be sprinkled around like confetti. And it broke my back. I had to throw cases of paper into it every 20 minutes.
Dealing with that device was like a Stephen King novel. It had a mind of its own and it could kill me should it decide to. I talked to it and babyed it and schmoozed it.
Edited by crazy March 13, 2021, 07:37:16 PM EST
This was definitely not print shop volume
This was in a college computer lab. Noobs like me didn't get to use the high speed printer. We rarely needed more than 2 or 3 pages at a time anyway, so we could wait.
I would sometimes be in there for an hour or more and no one fired it up. But when they did it sounded angry.
I'm pretty sure they had it behind a table so even if you were allowed to send jobs to it you still needed a staff member to pick up your output.
You were hearing the band spin
I'm not sure if you can visualize what's happening here. At least not if you've never seen the band.
The band is a strip of metal, circular, that is embossed with every letter of the alphabet and every character you want to print. It doesn't just have a single one for one mapping. Certain letters will be repeated at certain intervals such as the letter e because that is so common.
The hammer has to hit the band at the exact moment the desired character appears before it. There is a hammer for every character position across the page. That spinning band of metal never slows down.
The band gets placed on a track that allows it to spin in front of the paper and on the other side is the ribbon. The band spins really really fast. What you hear on startup is that band engaging and spinning up.
Also everything I just described is really strong reason for print shop personnel to never wear loose fitting clothing or ties. There are so many bits and pieces of this one printer that could grab you and just drag you in.
Edited by crazy March 14, 2021, 09:07:10 AM EDT
Edited by crazy March 14, 2021, 09:14:35 AM EDT
Hold on, mind blown
The printers I got to use were dot matrix.I apparently never got a close look at the output from the high speed printer, but I always thought it was a dot matrix with a horizontal matrix of pins instead of vertical that moved back-and-forth.
Okay, that would be called a line matrix printer. Based on the sound from the one video I could find where they were running one open, I'm guessing that's what I was seeing.
I'd love to see a band printer up close-ish. Your description of it sounds like something that shouldn't possibly work as fast as the videos I've seen of it.
Yeah that was old technology that still blows me away
No inkjet head. No spray of any sort. No laser. Incredibly fast mechanical things spinning around and having perfect timing.
Seriously, band printers are mind-boggling in their mechanical technical perfection. This is practically steampunk.
I would like to see the micro code that ran on those hammers and determined when to slam. It had to have some type of start on the band that sent a signal and then there had to be lookup tables and assumptions because there was nothing that was telling those hammer banks what was where, they had to figure it out themselves.
Speaking of old mechanical tech...
~ 125 BC
Modern people still haven't figured out all the details of how it worked (like did it have a part made of concentric cylinders, and if so, how were they made before the lathe was invented?).
The lathe is an ancient tool, dating at least to ancient Egypt and known and used in Assyria
https://ravimachines.com/history-of-lathe-machine/ greece as well
"Science is the belief in the ignorance of the experts" – Richard Feynman
What happens when something mechanical gets scaled up.
They took the whole printing idea and just made everything faster, sometimes by duplicating hardware (many more hammers), other times by increasing speed (paper feed).
Some of the "scaling up" is obvious: a lot more metal in a drum or band than a simple print head, but the difference in cost would be negligible next to how much they could charge rental (or even sale) for being able to make it print so much faster.
Far from the first time us humans have done this with technology. Modern gasoline engines can be insanely complicated, even before they got tiny computers everywhere. One of my favourite purely mechanical examples is Bosch's K-Jetronic fuel injection system, used by a wide range of performance engines in the 70s and 80s.
Another example I love is helical scan videotape. Four head drums needed four rotary transformers between the two halves of the drum. And later prosumer VCRs had way more than four heads...
Band printers were cool
OTOH, they were invariably used to print your bills, so.
Shouldn't possibly work as fast?
That is what I've been trying to impress upon you. Didn't I say really really fast a post or 2 above?
That band of metal is spinning around faster than you can see. But those hammer banks hit those letters at whatever moment as it spins by and chugs to the next line. That's the chugga chugga chugga noise going on.
From the human perspective that line printer has just printed that entire line instantaneously and has progressed to the next line. But from the microcode level you know there's a hell of a dance going on.
Yes, but I was picturing the line matrix
Still impressive, but not nearly as frightening.
Line matrix is easy
Line of data shows up into buffer. Map those points to pins that you're going to slam. Slam the pins. This is a simple bitmap manipulation. Move to next line. That is the simplest s*** in the world. Nothing impressive about it. I could code that in 20 minutes.
Compare that to having to figure out where those spinning band characters are versus what you are attempting to print and hit the hammers at the exact moment individually while those particular characters are spinning by. That s***'s mind-boggling. I'd have to take into account synchronization with the band. Then I'd have to know when a character was flying by at the micro second level. I'd have to take into account stepper motor timing. Oh, by the way, there were multiple bands. We had to change out the bands if we wanted different character sets.
Also, did you see the tape on the right hand side in that video? That is form layout control. There were series of signals you had to throw to the printer so it would go to a particular position on a form and those forms were controlled by those paper tapes. Paper tapes break easy.
Me with hardware control is like me watching figure skating
I know what *I* wouldn't be able to do, but not enough to know what's hard for people who know what they're doing.