As mentioned in a previous blog post, I've developed an interest in vintage computing. This has led to an interest in punched paper tape. I spent some time looking for a paper tape reader and punch but soon found they are rare as hens' teeth and extremely expense (several thousand pounds).

After much soul (and web) searching, I settled for a punched tape reader (only) and came across jmprecision.co.uk's reproduction OP-80A:





It's very easy to assemble if you follow the guide that comes with it. However, I made the twin mistakes of (a) not ordering the associated connector cable (sold separately), and (b) not actually having any punched tape to run through it. Thankfully, jmprecision offer a punched tape service, so after emailing a text file, ordering the cable and paying the fees, the punched tape and connector cable arrived a couple of days later.

Despite assembling it in a single afternoon, it took me a further 4 weekends to actually get it working. This was mainly because my level of electronic engineering comes from high school 35 years ago but also because I didn't RTFM (read the friendly manual). In particular, the line in the original OP-80A manual which reads: "To align the reader, place a low wattage incandescent lamp (15 to 60 watts recommended) over the reader and lower until the SP (Sprocket) LED comes on. The OP-80A is now ready for use." Had I read this earlier, I would've saved myself about 2 weekends of banging my head against a wall wondering why garbage was coming out on the Arduino's Serial monitor. The OP-80A is very sensitive to light levels. Again, RTFM.

Anyway, after much trial-and-error learning C, I finally got it to work on my Arduino Uno:




For anyone interested, here is the Arduino Sketch: