[GreenKeys] 32 and 33's

[Bob Camp]

Hi

I certainly saw a *lot* of PDP-8 and PDP-11 installations where the  
ASR-33 ran 24/7 as the console. I can *guarantee* that they never saw  
a drop of oil until the DEC guy dropped by. That was an every couple  
of months sort of thing back then. Most places went through a case or  
two of paper per month, unless they had a video terminal on the  
system. That's not a lot of use, but it is a lot of motor hours.

Bob


On Oct 6, 2007, at 2:03 AM, David I. Emery wrote:

> On Fri, Oct 05, 2007 at 09:11:56AM -0400, Teletypeparts at aol.com wrote:
>> They hold up far better than originally thought by design  
>> engineers.  I have
>> seen some TWX machines with 1500 hours on the meter.  Oil em every  
>> 100 hours
>> or so.
>
> 	That figure surprises me.   I am old enough to have been around
> the minicomputer engineering world back in the 70s when 33s were still
> quite common as consoles and low volume output and paper tape punching
> devices - we often kept them running at least 10-12 hours a day and
> sometimes 24 and while they weren't typing much during most of this
> time, the motor was running all that time and of course all the
> associated shafts, clutches and gears.
>
> 	I certainly saw many 33s last several years in this kind of
> service, which is certainly more than 2000-3000 hours a year.   Now
> granted most of those machines probably  sat idle with the motor on  
> for
> a hour or even several hours, typed a few lines and accepted a few
> keyboard commands and maybe then printed 3-4 yards of paper at most  
> and
> then went to sleep for the rest of the day with a couple of breaks to
> print brief two or three line messages.   And every once in a while
> maybe they'd be used to punch a tape or print something more extensive
> but not normally.
>
> 	But still I don't remember many breaking down in this service
> and I don't remember armies of TTY repair folks around maintaining  
> them
> either.
>
> 	This of course is very different from say a wire service model
> 15 banging away news stories virtually 24/7 or a weather service 28
> grinding out PIREPs and aviation weather reports and TAFs and so
> forth... one of those machines might easily chew through a roll of
> yellow paper in a day or more, while an engineering lab 33 even though
> running an equivalent number of hours might grind through a standard
> roll of paper in a month or even two or three.
>
> 	Most were retired when CRT based terminals replaced them or in a
> few cases higher speed dot matrix terminals such various DecWriters.
>
> 	
>
> -- 
>   Dave Emery N1PRE/AE, die at dieconsulting.com  DIE Consulting,  
> Weston, Mass 02493
> "An empty zombie mind with a forlorn barely readable weatherbeaten
> 'For Rent' sign still vainly flapping outside on the weed encrusted  
> pole - in
> celebration of what could have been, but wasn't and is not to be  
> now either."
>
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