Details about IBM's early 'scientific' computers

ben bfranchuk at
Tue Nov 14 22:45:19 CST 2017

On 11/14/2017 8:37 PM, Fred Cisin via cctalk wrote:
> On Tue, 14 Nov 2017, ben via cctalk wrote:
>> Computer Science seems to be mostly developed in the 1968 - 1973 time 
>> frame by average people with access with a (personal) computer with 
>> about 32K of memory.
> We could use some clarification of your terminology.
> Because MOST people do not consider any of the computers in 1968 - 1973 
> to be "personal" computers.

Well what do you call it then, when people rather than a VIP's
had access to a computer.

> Although the 4004 was announced in November 1971, commercial 
> availability of kits, etc. such as Altair, Imsai, wasn't until 1975.
Trying to design a TTL style computer from the 70's era,
the one thing that I can't find with common research, is what
memory was available back then and what prices. TTL,CPU's
and surplus I can find listed but what is MNO-4321 $15.95 a example 
listing. I can clock the CPU (74181's) at a good clip, but I can't
create the bus unless I can get REAL memory in my hands, or could in
the 1970's.
The CPU is 20 bits with 10 bit characters. Two large cards , one
the control and one the datapath make up the cpu. S-100 box size
computer with the blinking lights.
Cost wise I would say it would have been about the same ballpark
as early 8080 S-100 bus system. I am using 256x4 PROMS and think they 
came out in 1974 as well as 74LSXXX and Tristate logic rather than
OC buses.

> An individual TERMINAL connecting to a computer, perhaps, but computers 
> owned by an individual were rare.
> Admittedly, in 1962, Mauchly predicted "personal computer", and in 1968, 
> HP referred to the 9100A as a "personal computer".
> Having heard discussion of 4004 and predictions, in 1972, I left 
> aerospace (which had not completely recovered from a collapse), 
> declaring that I would get back into computers as soon as "tabletop 
> computers" became practical and available to me.

Just what is that? A PDP8 could be  on pedestal not hidden in a rack.

   (I did not foresee
> them being called "personal computers").  I intently watched the early 
> S100 machines, but didn't get back into computers until 
> TRS80/Apple/PET.  The first one that I owned was a TRS80 for $400 (I 
> supplied my own monitor and cassetter).
> (4K Level I, which I brought up to 16K, and paid for Level II upgrade. 
> Then Expansion Interface and Serial Port ("Radio-Shack 232"), supplying 
> my own drives, RAM, printer, etc.

I call them GAME machines.
I also tend to like Kilobaud better than Byte magazine.

>> All the new software development was Time Sharing of some kind, or a 
>> revised BETTER our NEW programming language, that
>> wants faster and larger core memory and the deluxe Binary-Trinary-Decary
>> virtual ALU*.
>> That why I suspect the state of computers is so dismal today.
> Yes, 1968-1973 had time-sharing for personal computing, but not 
> "personal computers"
> -- 
> Grumpy Ol' Fred             cisin at

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