
A database of SMS cards: The technology inside IBM's 1960s mainframes - kryptiskt
http://www.righto.com/2015/03/a-database-of-sms-cards-technology.html
======
hga
DEC got it's official start making their own versions of these (well, from the
TX-2 computer a couple of the founders worked on as graduate students):
[https://en.wikipedia.org/wiki/Digital_Equipment_Corporation#...](https://en.wikipedia.org/wiki/Digital_Equipment_Corporation#Origins)

So many computer companies had gone bust by then that, per their own
observations and the advice of the legendary Georges Doriot, "the father of
venture capitalism", they changed their business plan to doing that first, and
if they got enough business, to then do a computer with them. Hence the names
"Digital _Equipment_ Corporation" and "Programmed Data Processor", no
"computers" here. Or indeed no mainframes or 1401 class machines.

Heh, per the Wikipedia article, they sold a lot of these to other computer
companies who used them to test their own stuff. I suppose it doesn't
necessarily hurt to sell shovels while you do your own gold mining.

And, yeah, I remember these IBM modules. I obtained an decimal addressed
(units 0-9) very fast, like 124 inches per second 7 track IBM tape drive for a
computer center. It was filled with these boring, beige cards, DEC's looked
much better ^_^.

Hmmm, and the PDP-6 was a ... less than stellar success because it's CPU
wasn't made with these in the old fashioned way and was very hard to maintain
(see this PC board:
[http://ljkrakauer.com/LJK/essays/pdp6plaque.jpg](http://ljkrakauer.com/LJK/essays/pdp6plaque.jpg)).
Something they corrected with the first PDP-10, the KA-10, which used diode-
transistor logic and _huge_ wire wrapped backplanes.

~~~
kens
An amusing story about DEC's cards from Grant Saviers:

At DEC "deep sixing" NTF cards had real meaning. Since the mill [that held
DEC] had a mill pond, NTF repeat cards would often take flight out an open
window into the pond. Probably thousands of them there as Ken Olsen wrote a
memo that was posted along those windows, "Any employee who throws modules out
the windows will be summarily dismissed."

[NTF is "No Trouble Found", indicating a card that was returned as defective,
but worked fine when tested. If this keeps happening, destroying the card
would be very tempting. Compare with analog IC genius Bob Widlar, who would
"Widlarize" offending parts by pounding them to dust with a hammer:
[http://hackaday.com/2014/04/08/heroes-of-hardware-
revolution...](http://hackaday.com/2014/04/08/heroes-of-hardware-revolution-
bob-widlar/)]

------
xenophonf
Pictures three and four explain why so many sci-fi megaputers have drawers
full of cards^H^H^H^H^Hchips^H^H^H^H^Hcrystals that can be pulled out and
swapped around in order to fix a broken AI or something.

~~~
dalke
Agreed! It sure feels like HAL
([https://henryherz.files.wordpress.com/2013/12/05-robots-
hal....](https://henryherz.files.wordpress.com/2013/12/05-robots-hal.jpg))

I thought there was a similar style in Star Trek: The Original Series, but
while they had card-loaded computers, it wasn't as an array of cards. Their
hardware idiom is more like [http://tosgraphics.yuku.com/topic/409/The-
Type7-Console-Comp...](http://tosgraphics.yuku.com/topic/409/The-
Type7-Console-Computers)

ST:TNG has an example at
[http://vignette3.wikia.nocookie.net/memoryalpha/images/b/bd/...](http://vignette3.wikia.nocookie.net/memoryalpha/images/b/bd/Data_configures_isolinear_chips.jpg/revision/latest?cb=20120904004429&path-
prefix=en) but I suspect it was more directly derived from HAL than a 1960s
era computer.

~~~
xenophonf
It's carried over into modern sci-fi. Check out these pictures from _Stargate
SG-1_ (which is what first popped into my mind when I saw those photos):

[http://en.stargate-
wiki.org/wiki/images/b/b7/Tel%27tak_contr...](http://en.stargate-
wiki.org/wiki/images/b/b7/Tel%27tak_control_systems_crystals.jpg)

[http://en.stargate-
wiki.org/wiki/images/c/c0/Ha%27tak_Auxili...](http://en.stargate-
wiki.org/wiki/images/c/c0/Ha%27tak_Auxiliary_control_panel.jpg)

[http://en.stargate-
wiki.org/wiki/File:Ha%27tak_Glider_bay_do...](http://en.stargate-
wiki.org/wiki/File:Ha%27tak_Glider_bay_door_controls.jpg)

I'd love to talk to set designers on these shows to find out what their
influences were. I would not be at all surprised if these kinds of props
originate in the Daisy Bell scene in _2001: A Space Odyssey_ , and I would bet
any money that set in _2001_ was an extrapolation of the SMS card.

~~~
dalke
Here's a "logic module" from ST:Enterprise -
[http://www.startrekpropauthority.com/2011/10/star-trek-
enter...](http://www.startrekpropauthority.com/2011/10/star-trek-enterprise-
logic-module.html) . It's apparently from "In A Mirror, Darkly", where the
Terrans from the mirror universe acquired the Constitution-class Federation
starship USS Defiant. So it's definitely an homage to the 1960s series.

At some point it's hard to know the specific lineage. Consider "Land of the
Lost" from the 1970s, which had a control panel of colored crystals:
[http://img3.wikia.nocookie.net/__cb20150109000245/villains/i...](http://img3.wikia.nocookie.net/__cb20150109000245/villains/images/f/fe/Cryst2.png)

They are colored crystals in an array, though unlike the scene from 2001 and
the Babylon 5 images you found, these are not slotted.

I'm pretty certain there's a book or web site somewhere which goes into the
details of the design sense of at Star Trek.

------
larrys
"Information on particular SMS cards is surprisingly hard to find, so I made a
database of SMS cards, collecting information on 900 different cards. Given
the historical importance of SMS cards, I think information on this technology
should be preserved. "

I often wonder what motivates someone to spend the time to do something like
this. Extremely time consuming and with no obvious market for the information
relative to the time of "collecting information on 900 different cards". By
"market" I'm not saying "way to profit". How many people are actually
interested or need this?

I mean, look at this:

[http://files.righto.com/sms/](http://files.righto.com/sms/)

~~~
tr352
"There is much pleasure to be gained from useless knowledge." \- Bertrand
Russell

~~~
krylon
I think I have been waiting for this sentence for my entire life. My brain
retains irrelevant details like an inappropriate metaphor.

------
abe_duarte
I've been sort of a computer history enthusiast lately. Read about 7 books in
the last few months. I found this read very interesting. Always wondered how
these where built inside.

It seems IBM replaced this technology with SLT in 1964,
[https://en.wikipedia.org/wiki/IBM_Solid_Logic_Technology](https://en.wikipedia.org/wiki/IBM_Solid_Logic_Technology)
.

~~~
kens
SLT is an interesting technology since it falls in between discrete
transistors and integrated circuits. IBM's SLT hybrid modules were metal
packages 12mm on a side. Inside a module they put a few separate semiconductor
dies (transistors and diodes) and precision-trimmed thick-film resistors on a
tiny circuit board. It's like an integrated circuit on the outside but
separate components on the inside.

For a while, IBM built SMS cards that used SLT modules in place of the
discrete resistors and diodes. They needed to keep the discrete germanium
transistors though because the SLT modules were silicon-based. A picture of
one of these SMS cards is here:
[http://righto.com/sms/DGW.html](http://righto.com/sms/DGW.html) The result is
extremely space-inefficient, but it was a cheaper way of building backwards-
compatible cards.

