Archived posting to the Leica Users Group, 2016/06/26

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Subject: [Leica] Back ar work
From: jhnichols at lighttube.net (Jim Nichols)
Date: Sun, 26 Jun 2016 18:00:51 -0500
References: <49F06944-A24D-4BDD-9F52-19BABB82B5DC@acm.org>

Thanks for the memories, Herb.  My first encounter with a mini-computer 
was, I believe, a PDP-8, a descendant of your original.  It arrived as a 
part of the fuel control system for a turbine engine test, and, when the 
test ended, our Plant Engineering "hackers" looked for other 
applications.  We started with the two critical pressure measurements 
needed for an accurate Mach number calculation during operation of the 
16ft. Transonic Wind Tunnel.  By using the ratio of static to total 
pressure and the corrections determined during the wind tunnel 
calibration, the PDP-8 gave us real-time Mach number, displayed on small 
B&W TV monitors in front of the various operating personnel.  Things 
really developed from that small start.

Jim Nichols
Tullahoma, TN USA

On 6/26/2016 5:45 PM, Herbert Kanner wrote:
> My mail program went nuts last week. Twice I sent a rather long piece of 
> mail describing the circumstances around a Gallery picture and each time 
> the mail went into a black hole and the text had to be composed again. 
> This time I'm being smarter and writing and saving it first in a word 
> processor.
>
> OK. Don't remember what I last posted re health, but I was in the hospital 
> for over a week with congestive heart failure. Made a rapid recovery as 
> soon as I got home, and after a couple of weeks, returned to volunteer 
> week at the Computer History Museum.
>
> As a consequence of the loss of the Babbage Difference Engine, I rejoined 
> the group that gives twice monthly demonstrations of a working PDP1 
> computer (vintage 1960), the first ?mini-computer?, in fact, the 
> manufacturer (Digital Equipment Corporation) coined the term.
>
> The PDP1 is about the size of three household refrigerators. It's turned 
> on at the throw of one switch. It sold for $120,000. In the year it came 
> out, the manufacturer donated one to MIT. One professor permitted 
> ?hackers? access to it from midnight to morning. This was before ?hackers? 
> became a pejorative term. One of those hackers was Peter Samson, who 
> figured out how to make the machine play four-part music, and our demo 
> inclueds the opening of a Bach fugue. The other, Steve Russell, largely 
> wrote the code for the world's first video game, Space War, which later 
> became an arcade game.
>
> When I arrived at the Museum a week ago Saturday, I found the PDP1 team in 
> the cafeteria area enjoing a post-lunch bull session. I just had to take a 
> picture. We were all wearing our uniform red shirts. Note the guy on the 
> right; that's Steve Russell.
>
> http://gallery.leica-users.org/v/herbk1/L1000005_001.jpg.html 
> <http://gallery.leica-users.org/v/herbk1/L1000005_001.jpg.html>
>
> Please look ?large?.
>
>
>
> Herbert Kanner
> kanner at acm.org
>
> Question Authority and the authorities will question you.
>
>
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>



Replies: Reply from kanner at acm.org (Herbert Kanner) ([Leica] Back ar work)
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