Speaking of PPT (was: Re: Friden Flexowriter)

On 28 Feb, 2008, at 08:16, cctalk-request at classiccmp.org wrote: 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.