On 28 Feb, 2008, at 08:16, cctalk-request at
classiccmp.org wrote:
Message: 25
Date: Wed, 27 Feb 2008 23:38:42 -0800
From: "Chuck Guzis" <cclist at sydex.com>
Subject: Re: Speaking of PPT (was: Re: Friden Flexowriter)
To: "General Discussion: On-Topic and Off-Topic Posts"
<cctalk at classiccmp.org>
Message-ID: <47C5F482.14707.21D48412 at cclist.sydex.com>
Content-Type: text/plain; charset=US-ASCII
On 28 Feb 2008 at 7:49, Jos Dreesen / Marian Capel wrote:
The latest HP papertape reader I sold on Ebay
fetched all of 5
Euros......
I know that PPT readers can really zip right along, but what's the
fastest perforator ever made? Laser-driven, maybe?
Catching up on old messages.
The manuals for my ICT 1301 refer to the standard paper tape punch,
and it ran at 300 characters per second and had a check reading
station to verify every character punched before winding the tape
onto a reel. Unfortunately I don't have one of them but my 1301 does
still have one (of two) of the Elliott tape readers which runs at
1000 characters per second and which have a tape un-roller to prevent
any drag on the reader itself. At 1000cps, the tape comes out almost
horizontal from the reader and a bin has to be positioned correctly
to catch it. Even at full speed, the reader can stop on character
unlike the earlier Elliott tape readers, which was why when I worked
for Marconi-Elliott Avionics, all text tapes were punched with four
null characters after every line termination (ASCII CR-LF or
Flexowriter newline). Binary tapes were expected to be read all in
one go without stopping.
My own Flexowriters have round military style Cannon plugs for I/O
and use 110v signal levels designed for relay logic. A previous owner
of my 1301 has grafted on a large Vero board full of discrete
components, TTL and relays to drive one of the Flexowriters for
output, and an old ICT keypunch keyboard for input as well as a
smaller board to output to a Teletype BRPE (100 cps) paper tape punch.
The non standard online Flexowriter and keyboard are currently
disconnected and I control the 1301 the same way as 99% of 1301s were
controlled via the control panel, which is, I estimate, 4 feet wide
by 2.5 feet high. Most programs are small and I key them in through
the front panel as I can't find anyone to repair my IBM keypunch.