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New/DIY hardware to digitize punched tape for preservation

T4600C

T4600C

Experienced Member
Joined
May 10, 2015
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67
Location
Netherlands
Is there any new/DIY hardware that can digitize punched tape to a modern digital format?

Be it saving the raw 8-bits to a .bin file or saving the program to a .txt file in ASCII.

Because I acquired lot of punched tapes from the USA with the intent to digitize, preserve and make the contents available online.
Maybe we will find some interesting historical artefacts hidden within the holes, data previously lost to the aether but saved from the ultimate demise.

Thought this could be a cool project and help preserve a snippet of computer history.

I found this new OP-80a that seems like a good candidate? http://jmprecision.co.uk/shopping/pgm-more_information.php?id=149&=SID
Ideas if it would be possible to make an Arduino read the output and write to a file?

Some photos:
punched-tape-.jpgpunched-tape-2.jpgpunched-tape-3.jpgpunched-tape--4.jpg
 
In the commercial embroidery business, there have been punched-tape emulators for decades (e.g. Barudan). Same with CNC gear, where the iron costs substantially more and lasts substantially longer than the electronics. Back in the 1970s, I owned a dual-cassette unit whose function was to replace a paper tape reader/punch.
 
I have seen emulators, yes. But I need something to read mine.

An other option is to take the photographic route, using images of the tape stitched together.

johnr's Virtual Paper Tape Reader

www.johnr.uk www.johnr.uk

I will try to reach out to John and see if his program can help out here.

Not as cool as using the OP-80a clone but if it works it works.
 
I would say any of the optical readers designed for CNC machines would be fine for reading such tapes. Most will do 8-bit binary. I am in the UK and could read them for you.
An ARDUINO would be fine as the controller. There is a very nice GitHub project here:-

github.com

GitHub - dhansel/PaperTapeReader: A DIY reader for vintage 8-bit paper tapes

A DIY reader for vintage 8-bit paper tapes. Contribute to dhansel/PaperTapeReader development by creating an account on GitHub.
github.com github.com

.. I think the main challenge would be finding the Photo Diodes....
 
This would seem to be a good application for 'hole recognition' via a 'phone App...

A small handle and take up spool (with some mechanical arrangement for holding the paper tape in the same orientation and distance from the camera) and out should pop a file of the content...

Any post-processing could then take place after the initial 'scanning'.

Dave
 
g4ugm said:
I would say any of the optical readers designed for CNC machines would be fine for reading such tapes. Most will do 8-bit binary. I am in the UK and could read them for you.
An ARDUINO would be fine as the controller. There is a very nice GitHub project here:-

github.com

GitHub - dhansel/PaperTapeReader: A DIY reader for vintage 8-bit paper tapes

A DIY reader for vintage 8-bit paper tapes. Contribute to dhansel/PaperTapeReader development by creating an account on GitHub.
github.com github.com

.. I think the main challenge would be finding the Photo Diodes....
Click to expand...
The project at GitHub looks doable. I could probably source the parts, it may take a little while for all of them to get here.
May have to order at least 5 PCBs though of each, depending on the printing company. I don't think I will be able to sell the other 4 units that I could make?

I appreciate your offer, but I think this could be a cool project and a learning expereince for me too, and something to put on my YT channel.


daver2 said:
This would seem to be a good application for 'hole recognition' via a 'phone App...

A small handle and take up spool (with some mechanical arrangement for holding the paper tape in the same orientation and distance from the camera) and out should pop a file of the content...

Any post-processing could then take place after the initial 'scanning'.

Dave
Click to expand...
Johns virtual paper tape reader seems to be that. I can easily make any kind of still, video or webcam camera setup I want.

I suppose it could be done live, or from a video file. I got 60 or 120fps camera's, but I think the feed would have to be pretty consitent because it needs to track the smaller dots exactly to know which data dot row it needs to read next. A still solution may be better in this regard because the images can just be stitched in post to match exactly.
 
Chuck(G) said:
One of our forum members developed a project using phototransistors. I don't recall who, but it must have been close to 10 years ago.
Click to expand...
Most projects seem to use phototransistors of some kind, an electronic solution. The one from github and the OP-80a replica seem to be the most thought-out and documented.

I haven't got any experience with Arduino coding and teletype/altair formats coding so I would need help from the community with that.
 
Talking with Johnr about his virtual punched tape reader, it is looking like a really good and interesting solution.

I just have to develop a strict and consistent photographing/scanning and stitching workflow so the results will be accurate.

Some more info about the tapes from the seller:
"The tapes came from San Francisco and I believe that they were from a city related agency. Most of the tapes had a name/program written on them."
 
I'd first start by decoding one by hand and figure out what the content is likely to be. Could well be CNC or embroidery tapes--and so not of much interest to the general computer community.
 
Chuck(G) said:
One of our forum members developed a project using phototransistors. I don't recall who, but it must have been close to 10 years ago.
Click to expand...
That was me. It was inspired from the Raeco TPR-1 design and used phototransistors sanded to fit closely together and IRLED's that were resistor tuned until they stopped crosstalking, buffered and then fed to the input pins on an arduino. Testing proved that it could make good data reads at reasonable hand-pulling speeds but I have never been skilled at developing Arduino code and the project never left the hardware development/proof of concept phase. It's still sitting with the adapter plate on my LA120.
I got a lot of simple Arduino projects like that, looking at my list of To-Do's. :/
 
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Ah, I thought it might be your baby, but couldn't recall for certain. I never went into the Arduino thing--I program the old fashioned way of using a text editor and assembler.
 
The tapes have arrived. In fair condition. A lot of the plastic rubber bands have turned to goo, some of it even sticky like it melted. But possible to get off without tearing the paper.


From the writings on the paper, it appears to be a collection of games, math problems/processing, drivers, college programs and database processing. A few utility programs too, such as "Advanced Label Maker"

Quickly a few other titles: "Driver" "Guess" "Solve" "Jobo" "Data B" "Belle" "Stock" "Zero" "Cash D6 Style" "CHNZ 36" "PDPMOD XRUN" "LDATA" "TSCRG" "Library Proce Dures N Anual" "

A few tapes have written on them "PDP-8" and several got "College of the Redwoods" written on them. Dates range from 1972 to approx 1975-76.


The largest tape, which you can see in plastic on the lower left case has written on it "Wizard" so it is probably some kind of game.


Anyways, less talking, more digitizing. I still need to setup a workflow in collaboration with the writer of the virtual paper tape reader.

Two raw scans, stitched together:

Punch Tapes Lot #1 Test Tape 1.jpg

Processed by John for the VPTR:
NHPT.jpg

The result, perfect reading the first time:

SOLVE

9000 REM RANDY WONG 1/12/72
9010 REM TYPED BY MARK KURIHARA
9020 A=30
9030 RESTORE
9040 R=W=X=T=0
9050 DATA "END"
9060 DI

Success!
 
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daver2 said:
It doesn't do much though...

Dave
Click to expand...
Obviously not, it is only the very beginning of that tape, not the entire program.

But it is the beginning...

Still experimenting the workflow to get through these, trying things out.
 
Have you considered a cheap surplus reader? I have a Sanyo Denki 2702 reader and see they are still readibly available on eBay for about $50 including shipping. There's even one currently listed on Amazon for about $90 with free shipping to USA. Your shipping 'milage' may vary considering your location, though. eBay reports some as between $60 and $100 us dollars for shipping to your country.

The reader is basically a stepper motor and driver with a sprocket wheel and mechanics to hold the tape in place. Reading is via photo-diodes. It does mount nicely into a panel permitting solid support for running tapes through at up to 800 or so CPS (this of course depends on your driving hardware - slower should be easily accomplished by just not strobing as fast.)

Of course, I'm suggesting this without having tried it - there may be demons involved... Though the interface appears to be a simple parallel output with some strobes and status for control. If you are handy with a RPi, it should be pretty simpe to interface as it appears to be TTL data and control. Real (Japanese/English) manuals appear to be available for a nominal price.

I would strongly suggest, especially if you have old tapes that are potentially brittle, using a real piece of hardware that was designed for tape handling. I used an OP-80a (or its earlier version) decades ago on my IMSAI. Worked great but did manage to tear a particularly curly piece of old tape (old in 1983!) and had to patch it before retrying. I ultimately succeeded, but vowed to get a real reader for any more attempts.
 
Have you considered a cheap surplus reader? I have a Sanyo Denki 2702 reader and see they are still readibly available on eBay for about $50 including shipping. There's even one currently listed on Amazon for about $90 with free shipping to USA. Your shipping 'milage' may vary considering your location, though. eBay reports some as between $60 and $100 us dollars for shipping to your country.
Click to expand...
All the listings I'm seeing start at $50USD with anywhere between $55 and $90usd for shipping and that's just to Canada. :-/
 
I thought about getting a physical machine and programming an Arduino to save the data.
But that would be more expensive, and I do not have the mechanical/programming skills/knowledge to make something like that.

An other try by John on one of my other tapes, labled "Wizard"
It is by far the largest tape, and probably some kind of text based fantasy game.

With John I have developed a workflow where the resolution and exposure is all correct right out of the scanning software, all that is left is stitching the framelets together.
John will be releasing the VPTR at one point.

Punch Tapes Lot #1 Test Tape 2 Wizard 1 Processed.png

This read perfectly the first time, no errors. The result:
10 DATA "//NOTHING SPECIAL 1"
20 DATA "GAUNT"
30 DATA "EMACIATED"
40 DATA "ADJURE"
50 DATA "COMMAND EARNESTLY"
60 DATA "DECANT"
70 DATA "POUR"
80 DATA "RENUMERATE"
90 DATA "PAY"
100 DATA "INNERVE"
110 DATA "INVIGORATE"
120 DATA "EXORCI
 
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