[GreenKeys] One-Hole Paper Punch

[Jim Haynes]

On Tue, 21 Apr 2015, Roy Morgan wrote:
>  In the picture you sent right in the middle is a one hole paper punch.
>  It is mounted on some sort of stand or bracket which is extra, no doubt
>  a WU addition.

One use for such a thing is to cut a notch in the edge of paper tape
so that when the tape passes through the reader the tape-out detecting
pin will go through and stop the reader.  I would have to do more
research than I'm willing to do at this moment to find a citation for
that use.