Show and Tell 1306

Among the wreckage we found a fragment on which had scratched:

I used this gadget, or something similar to it, in the 1970s. In those days it was called a "Unipunch". It could be used in a variety of ways, you could punch holes with the little hand-held die, cut the tape with the gilloutine, and use little perforated sticky patches to join two tapes.

The patches came in two flavours, those that had all the holes punched, and those with only the sprocket punched. The fully punched ones were used if you had to splice in data, the sprocket-only variety if you could get your splice to come in leader.

It was quite common to find tape-copy programs that would punch 10 nulls after a line feed to give you a bit of leader in which to splice. You could - and I have - program this way. You typed out a first attempt at your source on an ASR33, using it as a keypunch, tried it, and when you came to debug you punched new bits of tape and spliced them in with the unipunch. When the tape got too tatty you copied it from photoelectric reader to high speed punch, and this time you got the little bits of leader, and went on again.

You seem to be missing the other punch. There should be two of the little prodders, one for sprocket holes and the other for the larger data holes.

In extreme cases you could even program with it. I - just once - managed to put a binary path in the PDP-11 abs loader with one.