Paper tape readers

[pentium]

It's not the most modern, it's not the most compact but for them good ol' 8-bit systems they are truly unique.
I was looking through a book talking almost completely about mods and other cool things you can do with your TRS-80 (dated 1982) and one cool thing I came over was a partial schematic for a paper tape reader. That had me thinking about what to do next.
I then saw this and realized that I could finally make some use of my jar full of 555 chips and other cool IC's I got when our school was cleaning it's shelves.
Now even though I only have a little bit of google, that manual and the small amount of photos and partial diagrams that made mention to the Raeco TPR-1, I still need info on some of the precise parts.

-What's the LED spacing between holes? Is a special LED needed?
-Punch tapes are 1" wide, right?
-What speed should the tape be fed at?

Uh oh. There goes the bell. I'll finish off later.

[stretch0069]

Re: Paper tape readers




you need a girlfriend..........









actually, sounds like something cool to do just for the hell of it. my problem is that i'm a good project starter.....baaaaaaad project finisher.

[gonzo0815]

Re: Paper tape readers

i totally agree with that.

[pentium]

Re: Paper tape readers

you need a girlfriend..........

No. First a NeXT cube and THEN a girlfriend.
I looked over the schematics again and found that there were a few component listings hidden off to the side. I managed to copy it down onto a sheet of paper and I now have the schematics and a full parts list. The only items I worry about is the two IC's (4502) the lamp block (MRD150) and the track that the tape lays on while it is being read. That looks like it would need to be machined. Besides those parts, it's a very simple project (Only two IC's and the rest is just resistors, framing and soldering.
If my scanner was working I would post it.

[Paul S]

Re: Paper tape readers

I used to run CNC (Computer Numerical Control) machines in a machine shop. I went to night school to learn to program them. They first taught us how to program the old NC machines that used paper tape to hold the programs. We learned how to read the tape directly, just by decoding the punched holes.

Maybe you can find an old NC tape machine and use the reader from it.

I may still have my old schoolbook from that class.

[pentium]

Re: Paper tape readers

Maybe you can find an old NC tape machine and use the reader from it.

Do you know how rare it is to find the paper tape itself, let alone the reader?
I wonder if I can not only interface this with the TRS-80 but also my apple IIe, Vic-20, C64 and one of my older pc's.

[Paul S]

Re: Paper tape readers

Did you know that there is a wiki on paper tape?
http://en.wikipedia.org/wiki/Paper_tape

Also, here's some images of the machines used to punch them.
http://blinkenlights.com/classiccmp/friden/

Most of the paper tape machines were tossed in the junk pile years ago. But, some tech schools may still have one in a back closet . Check with the CNC training departments.

P.S. I found a source for tape.
http://www.wncsupply.com/paptape.html

[pentium]

Re: Paper tape readers

Hey thanks for the info.
I have been given clearance to use the milling machine once my metal shop project is done. I can then make the paper track which will keep the paper and the sensor aligned. I still need to know how wide the average roll of paper tape is and the spacing of the holes and their sizes.

[Paul S]

Re: Paper tape readers

There was a link at the wiki to paper tape specs:

http://www.srcf.ucam.org/~jsm28/ECMA-10/
There are two sizes 1" (25.4mm) and 5/8" (17.45mm)

There even is a description of the tape reading mechanism, with exploded view diagrams.

[pentium]

Re: Paper tape readers

How did I miss that link?
Yay! I now have all the info I need to make the paper track.

[Paul S]

Re: Paper tape readers

I'm not sure how you will make a punched tape, but the machine that I used, in my CNC class, looked something like this:
Teletype ASR33

or this:
Flexowriter

I came across this page of a CNC book, it has some more tape specs:
CNC Progamming Handbook

As a side note, I actually worked at a company that made some of the original NC Tape Machine Centers, Kearney & Trecker. It was in the late 1970's, and tape machines were no longer being made. But they had a large number of them in the shop, that they used to make parts for the newer model CNC machines.

I ran a DeVlieg Jigmill and did the final machining on the gearbox (knee) for there line of manual milling machines ((K&T milling machine). When my machine was down for a while, I was assigned to clean the offices. I remember the room where they punched the tapes. They used a plastic type tape (Mylar?) and the little pieces that were punched out were all over the carpet. They were very difficult to vacuum up!

That's about as close as I got to the tapes.

Paul

[pentium]

Re: Paper tape readers

I heard our local archive has a few rolls of punched tape but no reader.

Heh, I like seeing how paper tape rally helped CNC machines in the early days. So far that's the only place they seem to have been used en mass.

[PeteS in CA]

Re: Paper tape readers

I remember seeing board testers being run by paper tape when I was at Kaiser Electronics (now part of Rockwell, iirc). This was back in the late 70s. Kaiser made/makes display avionics for military aircraft. The project that used the tester was for the F-14, which means the machine was an at least an early-mid 70's design. I don't remember whether a version of the tester was used on boards for the 60s-vintage A6 project. I worked on the F-18 head-up display (I saw HUD S/N 001 go out the door) and A-10 projection unit projects.