[GreenKeys] Help with IBM Printing Selectric

[Robert Nickels]

On 4/26/2019 1:46 PM, Bob Rosenbloom wrote:
> Look here:
> http://www.bitsavers.org/pdf/ibm/typewriter/selectric/
>
> There's quite a bit of info on the I/O Selectric.

Sure would have come in handy about 40 years  ago!   A buddy had built 
an IEEE-488 controller to interface an I/O Selectric to his Tek 4051 
graphics computer which he built "one piece at a time" while working for 
Tek, and I wanted one in the worst way.  I ended up buying one from a 
surplus outfit that I think used them for a hotel reservation system.   
It had an expanded-width housing (painted dull red) with an array of 
extra switches on the side - I stripped everything but the solenoids out 
and built a very simple parallel interface and did all the timing and 
tilt/rotate control in software, which at the time was BASIC.   It was 
crude but it worked quite well at around 10-11 characters per second, 
slightly slower than the 14.1 cps that was possible using something like 
an IBM 2741 with it's EBCDIC serial interface.  (Remember why 134.5 
baud, and APL?)

I had fun doing it and showing it off but eventually it was replaced and 
one of the epoxied-in and Bondo-filled panel fillers fell out and the 
red undercoat was starting to show through the spray-can IBM blue, so it 
ended up in a dumpster at moving time. True letter quality print was a 
source of pride at the time, but I don't have any desire to do it again!

73, Bob W9RAN