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Comment by GnarfGnarf | Hacker News Reader

Their main problem will be finding card stock. When compiling, the binary object is output on punched cards. They will need lots of blank Hollerith cards for compiling and testing. Not a lot of places make punched cards anymore.

Also, need card punches for input: IBM 029, Univac 1701. Will also need ribbon for printing readable characters at top of card.

Card readers are high-maintenance equipment. The cards are fed at high speed with a picker knife that needs precise adjustment. The card stock is sensitive to humidity. If it swells, it doesn't go through the card reader.

I wrote Assembler in the 70's on Univac 9300 and 9400's, 360 clones.

I see small lots of cards on eBay for astronomical prices. They probably wouldn't even work because of swelling.

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The 3 guys work at the National Museum of Computing in the UK. They may well have access to cards that they can use as templates.

Cards are widely available, even new.

Their main problem will be getting it running! For example: if there are germanium transistors in it, they often fail, and you can't get modern replacements easily.

Every board will need to be checked component by component and it will have to be powered up very carefully. Just getting everything connected together and damaged cables repaired will take a long time.

Not true! USSR produced germanium transistors much longer than the west. Large quantities are available on eBay. For example here they are being used for radio repair:

https://www.youtube.com/watch?v=wet7QameYc4

The main annoyance is the shipping delay.

One interesting thing I learned is that the metal can germanium transistors are often more reliable than the first generation of silicon transistors: those domed-top epoxy ones are all terrible.

Correct. For a Fuzz Factory guitar pedal I built instead of bought, everywhere I read online said to use the AC128 germanium transistors for a better sound. I got a pack off eBay for less than $10 shipped from the Czech Republic.

Couldn't you make something that emulates the punched card reader but just reads and writes them to files?

These actually exist (or used to) for paper tape.

Until the early 80's a lot of CNC (Computer Numerically Controlled) machine tools (e.g., milling machines, lathes, planers, etc.) were programmed using paper tape. Large machine tools are built with literally tons of cast iron (cast iron has excellent vibration-damping characteristics and is a fairly good bearing material) and run for decades: there are still WW2-vintage machines labelled "PROPERTY OF WAR DEPARTMENT" humming along in small machine shops. Not surprisingly, the owners of expensive capital equipment didn't want to just up and buy new ones that were programmed by floppies or over RS232, etc. So an industry sprang up to convert the paper tape readers to take electronic inputs and emulate paper tape.

I remember at my first job, being approached by our PCB vendor who had a CNC drill that read paper tape. He was looking for a way to bypass the tape reader and input RS-274 drill data from a floppy drive. Would have been a fun project, but my boss passed on it.

In fact, there are a couple of small companies selling thumb drives with IDE interfaces that plug into the floppy drive port so you can load code on a thumb drive, but the machine thinks it's reading a floppy.

You don't need special hardware at all to read punchcards now that I think about it.

It would be a machine vision project to build a punchcard reader that takes images from a camera, flatbed scanner, etc.

Something like this, perhaps! http://zulko.github.io/blog/2014/02/12/transcribing-piano-ro...

One of my first jobs was working with devices that emulated paper tape via a serial connection to talk to CNC machines that had a device installed into the old papertape reader to give it a serial port instead. G-Code was loaded by one of the old terminal emulator serial connect software (Procomm? Telix? I can't recall) via a cheap old PC and modem. The machine didn't know it wasn't paper tape. They will probably need to hack up something along the same lines to pretend to be a card printer/reader. Sounds like a job for a Raspberry Pi or similar.

Could you not cut your own cards with a hobby die-cutting machine? I have some old punch cards and a Sillohouette Curio, I don't see why it couldn't work given a good sharp blade and a fresh cutting mat. That kind of cardstock cuts like butter, too.

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