Several Paper Tape and 40/80 Column Punchcards are showing up on eBay and there’s a few instructables starting to popup as well.
What could we make with one of these at the space?
I have the paper tape reader I got off of the Freebie Shelf. It has a parallel interface. I have not tried to see whether it works.
Parallel? nice, we might be able to hook that up to one of the CBM or apple systems. From there we could write a program that would read it in and convert to… ascii? DSP/PCM?
Would still need to figure out what to do with the data after that.
I have not tried search for documentation on the 'Net. I was going to use an Arduino to try to read from it.
Edit: from there, transfer the blob to a PC to run various disassemblers against it.
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If we have the reader available, why don’t we make the group project a paper tape punch. That way we don’t have to worry about the data format at all, we simply create it.
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I just dug it out of the truck. It is an OAE OP-80A. I’ll look for doc on it and try to get it working.
Edit: comments online seem to indicate that this was a fast and reliable unit compared to many others which were available at the time.
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I was thinking a nitinol based actuator driving lever controlled punches. Or possibly sub micro servos controlling the punches with cams.
Blank paper tapes came from the factory with the sprocket holes already punched. There are actually nine rows of holes, not eight as you would expect. The ninth row of sprocket holes provide synchronization for the punch and the reader. The sprocket holes are smaller than the other holes, helping the construction of optical readers. By the time light can pass through the sprocket hole, the other holes are lined up, so detecting the sprocket hole is the perfect way to generate the data clock.
Are commercial blank tapes still available? I hear that some old CNC equipment still uses paper tape, so maybe it is still being made.
If we punched paper tape from scratch, what stock do we start with? It has to be somewhat durable, yet soft enough for the punch to go through it cleanly.
For short term use we could use a receipt printer to produce raw tape with a black square timing mark and simply use friction wheels to drive.
Back in the late 70’s, early 80’s, I used commercial mylar “paper” tape to startup my Imsai 8080. I remember it having the timing holes prepunched. I used the tape punch at NTSU in Denton to punch my tapes… but I doubt they still have one. 
Mylar tape wasn’t that pricey back then, but it did have a premium. I used it because it lasted MUCH longer than regular paper tape… and paper tape was my “boot drive” on that machine.
I suspect we could use the thunder laser to cut out and “punch” tapes of a few feet long, which could be spliced together as needed.
Jayson Woods, John Gorman, Brian Terry and I did some experiments into making our own player piano rolls. The laser cutter did not do so well. The vinyl cutter (cutting on paper) showed potential. Those were rectangular slots instead of round holes.
If we used a laser, we would need a cleaning pass after cutting so that soot does not foul an optical reader.
I am not thinking about using time holes, but marks on the receipt paper for timing. Use stepper driven friction wheels to move the paper in a controlled way. Only punching would be for the data.
I wonder how hard it would be to machine some tooling steel and make the tiny punches. They could be solenoid driven by an Arduino to make the holes and another Arduino could use simple optics to read it.
I have a large lever arm paper punch that will punch through 10 to 20 sheets at a time and its design could be inspiration for the miniature punches.