[GreenKeys] Can You Identify This reader-punch unit?

[John Nagle]

 > From: Don Robert House [mailto:k9tty at dls.net]
 > Sent: Friday, September 25, 2009 8:42 PM
 > To: Chris Elmquist
 > Subject: Re: Can You Identify This reader-punch unit?
 >
 > On 24 Sep 2009, at 9:25 AM, Chris Elmquist wrote:
 >
 > Hey Guys,
 >
 > Can anyone identify the punch unit on this website,
 >
 > 
http://www.ericmackonline.com/ICA/BLOGS/emonline.nsf/dx/nonmagnetic-digital-storage-at-10-bytes-per-second

There are clearly some Teletype components there, but it's not part of a
Teletype.  It's not a Friden Flexowriter component either.  However,
many early computer manufacturers used Teletype punches in their own products.

I can't find an exact match yet.  But it may be an early DEC-era peripheral.
Take a look at

http://highgate.comm.sfu.ca/~djg/htdocs/pc04/small/punchside.jpg

That's a later DEC high-speed punch, but note the similarity of
the layout.  Both are set up for motor drive through a timing belt.
Note the big flat-toothed sprockets.  In Mack's device, the
sprocket is there, but the belt and motor are missing.

Mack's device requires external electronics.  Note the optical interrupter,
the metal timing disk with slot, and all those wires going to the
DB-25 connector.  This thing is intended to be driven by something
with electronic buffering.  So it's part of a computer peripheral.

The DEC high speed punch mentioned above shows a somewhat similar
mechanism with its support hardware - power supply, motor, toothed
belt, and drive electronics.

After looking at the DEC hardware pictures on line, I can't find any
exact matches in DEC gear.  It may be from one of DEC's competitors.
Probably dates from the late 1960s or early 1970s.  Earlier than
that, and it wouldn't use an optical interrupter for timing.
Later than that, the drive electronics would be small enough they
would have been packaged with the punch.

				John Nagle