Back in the 1980s, printers were expensive things. Scanners were rare, particularly for the home market, because home computers could barely handle basic graphics anyway. Back in these halcyon days, an obscure company called Thunderware built a device to convert the former into the latter. It was known as the Thunderscan, and was a scanning head built for the Apple ImageWriter dot matrix printer. Weird enough already, but this device hides some weird secrets in its design.
The actual scanning method was simple enough; the device mounted a carriage to the printer head of the ImageWriter. In that carriage was an optical reflective sensor which was scanned across a page horizontally while it was fed through the printer. So far, so normal.
The hilarious part is how the scanner actually delivered data to the Macintosh computer it was hooked up to. It did precisely nothing with the serial data lines at all, these were left for the computer to command the printer. Instead, the output of the analog optical sensor was fed to a voltage-to-frequency converter, which was then hooked up to the handshake/clock-in pin on the serial port.
The scanner software simply looked at the rate at which new characters were becoming available on the serial port as the handshake pin was toggled at various frequencies by the output of the optical sensor. Faster toggling of the pin indicated a darker section of the image, slower corresponded to lighter.
Interestingly, [Andy Hertzfeld] also has his own stories to tell on the development, for which his software contribution seems to have netted him a great sum of royalties over the years. It’s funny to think how mainstream scanners once were; and yet we barely think about them today beyond a few niche uses. Times, they change.
Thanks to [J. Peterson] for the tip!
In 1975 Exxon introduced the Quip fax machine, which used an external acoustic coupler. We had one at Q1, and I interfaced to it and used it to scan photographs into the system.
Exxon made a fax machine? Wow what.
Old story, but a good one. Converting a matrix/wheel printer into a grayscale scanner was being described in one of the old PC tinkering books I have.
It was called “PC Bastelbuch” I believe.
It was a DIY solution, using a photo diode mounted on the printer head. The diode could have been wired to the gameport, I believe.
The Program was written in QB 4.x, I believe. It used PCX format and was very interesting.
It used the parallel port printer to move the head, without writing anything, actually.
If you have more technical details and even sourcecodes do not hesitate to share them. Very interesting
Sure, just checked. The book’s ISBN is 3-89090-331-1. It’s from Markt&Technik publishing company.
The hardware consists of 2 red LEDs for lighting besides a photodiode BPW 17 N and another LED facing upwards as power indicator.
It’s mounted on a piece of veroboard (3×1,5cm). The mounting is a copper PCB of 4×1,5cm (where the veroboard is mounted on).
The photodiode goes to one analog channel of the gameport (X or Y). The gsmeport also serves as a power source.
The scanner has a resolution of 47 DPI, AFAIK. The document to be scanned has to be 9,7×8,2cm or bigger.
PC can be an original 4,77 MHz model, with Hercules graphics. Matrix printer should run at 120 chars in normal mode.
Of course, VGA graphics can be used, too. Either by using Hercules emulation (old VGAs had a DOS mode utility to switch to Hercules) or by altering the source code.
That seems reasonable, considering the analogue on the game port, although not always the case. I remember tinkering with something along those lines, but I used a resistor ladder on the parallel ports input pins instead. I wrote a little bit of asm to do the reads and writes that could be called from a dos batch file with a few peramaters.
I used to have a dos text reader called a datapen or something similar, that inspired me to make my own version. It plugged into the parallel port and ps2 ports, with a battery pack that clipped on the parallel port connector. and had a low resolution camera and a wheel for distance encoding. Needless to say although it worked it was pretty awful if you weren’t precise enough. I don’t think I ever finished the project, technology moved on.
“It’s funny to think how mainstream scanners once were; and yet we barely think about them today beyond a few niche uses. Times, they change.”
Are you talking about these printer hacks, specifically? I would say scanners are not niche, but ubiquitous in multi-function printers (MFP). I use mine several times a week. Important paper goes right to the digital cloud.
In a “Mars/Venus” situation, I *only* scan with my MFP and my wife *only* prints.
“It’s funny to think how mainstream scanners once were; and yet we barely think about them today beyond a few niche uses. Times, they change.”
Not really, handy scanners were available to all computer users since the 80s. They were just less common.
Just check early Windows 2/3 programs. In their ‘About’ dialog, there are not seldomly digitized profiles of the authors to be found. They’re likely being digitized with a simplistic scanner of the day.
Speaking of, my dad had one for his IBM PC, it was bundled with a copy of Dr. Halo, I believe. It shipped with an interface card.
On C64, there were a lot of handy scanners, too. In Germany, the Handyscanner 64 by Scanntronik might have been known.
The company also offered products similar to what’s in the article (Superscanner III).
Then there was DigiView for Amiga. It’s from 1986/87, I believe. It’s a frame buffer device, to interface with a b/w camera or VCR (pause mode).
Anyway, I can understand where this mistake is coming from and can forgive.
There’s a lot of generalization going on today and we want to believe that we’re improving all the time. Odd things that aren’t mainstream don’t seem to fit in somehow are being seen with scepticism. That’s just natural, I suppose.
Personally, I had owned a handy scanner (color model) in the Windows 3.1 era. Before internet access was common. It was in a time of online services like AOL and CompuServew, which did their own thing.
Sorry, what I meant to respond to was “Times, they change”.
Scanners had been around since early days of Personal Computing and they’re still around.
In their simplest forms, they used to be fax machines.
Some users used them to get an image into the PC.
By using a fax software and a modem/acoustic coupler it was possible to use a fax as a low-end scanner.
And as a printer, vice versa.
C64 users did that, too. There’s even a software for GEOS (geoFax) to do that.
In our modern days, scanners and fax devices are still around, too in the form of multi purpose devices.
Those telephone/scanner/printer devices do often have fax functionality, too.
And they’re needed, still.
Digitalization (IT aka EDV) hasn’t reduced paper works, but increased it.
We’re working with more forms than ever.
At least here in my country.
So scanners and OCR software are very important, still.
“It’s funny to think how mainstream scanners once were; and yet we barely think about them today beyond a few niche uses”? That’s a surprise to me. I would have easily believed that people may not use the function very much at home if none of the entities they interact with still use paper, of course. I still expected families would probably have the function on a multifunction printer, though. Did everyone truly get rid of theirs and switch to just using a phone camera?
While photos with a phone and heavy processing can be pretty legible, they don’t let you make a seemingly-exact copy like you can by scanning. And of course at work, if you have a bunch of paperwork to scan into a system, a dedicated scanner with a document feed that works with your system’s old twain or isis interface can be very convenient, also.
Disclaimer, I may be atypical as I also find that a typewriter is occasionally nice to have in the closet. Sometimes you may have forms to fill out and return to your kid’s school, or other paperwork to do that must be on its original paper, but can be typewritten onto rather than getting a cramp in your hand trying to write neatly. Or speaking of school, maybe there’s assignments where they want to see scratch work on paper, which goes back to the scanning thing.
Hi there. I can somewhat relate to the last one.
My grandma’s mechanical typewriter was being used all the time at home to fill out original documents/forms.
It was archaic to do, maybe, but the result was somewhat clean and tidy compared to using a ballpoint.
I’ve also used that typewriter in my school days to write an essay (higher classes, of course). Later on, I’ve used a PC for that purpose, too, though.
The typewriter was more direct, though. You could fill out parcel labels with it, for example. Which was nice, because it increased machine readability.
That’s important, because otherwise if OCR fails, a human staff member at the postal office has to decipher things manually, which delays transport.
PS: Another thing that comes to mind.
CD-ROMs and public domain software.
Back in the day, photos in PCX/GIF/TGA format were popular.
They had been shared via BBSes and 5,25″ floppies, even.
Now, how was the digitizing being done, if not via scanner and\or frame grabber?
I really think that scanners were known to most users in the 80s, but that not each user had one at home.
Same with modems, I think. Nearly every user knew what it was back then, even if only a small fraction actually had owned one.
Typewriters are good in giving forensics something to work with. ;-)
Printers are no different, I suppose? I heard ink printers do print a serial number of some sorts (faint bar code). Hand writing can be recognized, too.
Colour laser printers apply very fine codes yellow dots on the printed paper, which identify the exact printer, time and date of printing, and other stuff. You can see it if you scan then zoom on a white “unprinted” area.
Decoders are available online.
Depends what you’re comparing to. I’ll speculate that getting a printer secondhand for cash and destroying it after printing may be the best option. With a typewriter, you’re potentially the only person still using one that they can find. But unlike handwriting, you don’t have to unlearn a typewriter, just get rid of it, and you have less accidental influence on the shape and pressure the letters have, especially if it’s electric and you adjust the pressure randomly.
As a physician I used to use a typewriter all the time to fill out various hard copy forms for discharge. Like for care facilities, jails, etc. it was about the only way to get the printing to line up with the arbitrarily spaced lines and boxes on forms.
.
At home I have a physical typewriter because it handles heavier paper and cardstock pretty well compared to the computer printer. I use it for thank you notes on nice stationary which I acknowledge sending thank you notes is archaic anyway but everyone loves it and I like doing it.
Maybe I should do something like that. There’s an old way to fold letters I have used before to turn a piece of paper into its own envelope while being easy to seal – maybe with wax but definitely with regular tape, and it should be compatible with modern mail. Could be good for when you just can’t think of a good personal gift idea.
In 1987, inspired by that ‘scanner’ but way too poor to afford one, I mounted a LDR with a small magnifying lens and aperture on the printhead of my dot matrix printer. I read the analog signal with the joystick port.
Print a space, read analog value, repeat.
Slow, minutes per page, but worked great. Resolution about what you can expect: around a millimeter. Too coarse for text, but OK for full-page images.
Just as well the resolution was not very high: a single image could fill a 1.44 MB floppy.
I actually had one of these. It worked surprisingly well.
Me, too. I worked in a museum, and frequently used a Thunderscan for purposes like digitizing the hand-drawn work of our staff artists so that it could be used to create computer graphics.
Wait! I forgot the name of the sensor, but I had built something similar in the 80s. I used a sensor originally from a bar code reader directly giving logic level output. So I only got one bit at a time. In test runs I did not remove the printer head, found a way to move the head without printing and after the 1st scan I was convinced that it’s possible, but way too slow to be worth it and dropped that idea.
I had a Thunderscan (and IW2) back in the day, and given the home user alternatives, it was a nice product. Thanks, Andy!
When I was a kid, we had one of these for the wide carriage ImageWriter hooked up to our Macintosh 512K! 😃
I was an owner/user of this scanning device, and one thing that I liked was the ability to print a fairly large, multi-page poster by using track-fed paper. That paper was fairly common then.
Aha so that’s what that was… I remember my computer science teacher (H. Cooke, hi there if you see this!) was playing with one of these when the local high school got its brand-new computer lab with a bunch of Apple IIgs machines, in 1987 I think. So it’s not only a Macintosh thing; AFAIK the school didn’t have any. The school had also gotten an original LaserWriter. That was the first time I saw either a scanner or a laser printer.
I built something like this for reading and categorising expensive master etched Holographic Optical Elements (those fancy pictures that you can now get 30 of for £1 on a laser pointer, produced from those masters like vinyl records were) back in 1999! Move the steppers, take a reading from the point sensor, repeat. Final year project for my degree.
“yet we barely think about them today beyond a few niche uses”? I disagree, the company I work for has many scanners, in daily use yet. Photography doesn’t beat scanners in many applications.
“Clean” document scanning eliminates translation errors. Our first scan of a PCB we want to copy is with a scanner (after coating the PCB with dye to highlight the tracks. Once scanned the output is loaded into an appropriate program.
We scan physical piece parts prior to preparing NCR mechanical instructions, sure beats doing it manually.
Minutes ago I used my scanner to copy none of the Chinese instruction sheets they love printing inhj 6-7-8 point characters.
If my scanner died I would be up a well-known creek.