10 Jun
2026
10 Jun
'26
4:32 p.m.
Didn't show up on the list, so re-sending it:
---------- Forwarded message ----------
Date: Wed, 10 Jun 2026 12:14:39 -0700 (PDT)
From: Fred Cisin <cisin(a)xenosoft.com>
Subject: [cctalk] Ramac : The real first disk drive? (Was: Floppy disk
The first known and recognized disk drive of ANY type (hard disk preceded
floppy) was the Ramac, 70 years ago, 1956
https://www.computerhistory.org/storageengine/first-commercial-hard-disk-dr…
First one shipped was to Crown-Zellerbach Paper Company
CHM says June;
EDN and Google AI (Gemini) say September 13, 1956
https://www.edn.com/ibm-intros-1st-computer-disk-storage-unit-september-13-…
But, Gemini seems to also hallucinate RAMAC as being a company!
"At the 1958 Worlds Fair, RAMAC showcased its revolutionary random-access
capabilities by answering world history questions in 10 different languages."
(There was no Ramac Company exhibiting at the 1958 Worlds Fair)
Ramac had fifty 2 foot diameter double sided platters, and could hold a total
of about 5MB. Modern drives can have even higher density!
I have a crashed Ramac platter, that I have made into a patio table, with the
platter under glass.
In 1959, Nikita Khrushchev visited USA for 12 days, to try to calm the cold war
a bit.
On September 19, 1959, he tried to visit Disneyland,
State Department and Disneyland consulted with each other, and they would not
let him go to disneyland! Khrushchev was angry about that:
"What is it? Is there an epidemic of cholera there or something? Or have
gangsters taken over the place that can destroy me?"
Frank Sinatra hosted a massive celebrity lunch for him at 20th Century Fox
Studios, attended by Marilyn Monroe, Shirley MacLaine, Gary Cooper, etc.
When Nina Khrushchev expressed her disappointment about Disneyland, Sinatra
said to David Niven, "Hmm, tell the old broad that WE will sneak them in".
Apparently that visit didn't happen, or was very sneaky.
I remember a New Yorker cartoon that showed a soviet sub surfacing off-shore to
sneak him in.
Y'know, if they hadn't banned them from Disneyland, the entire Cuban missile
crisis would have been a lot less hostile!
To make up for not letting him go to Disneyland, the State Department, on
September 21, 1959, took him to San Jose, to tour IBM's facility, and see
Ramac.
S'posedly, Khrushchev was more impressed by the operation and efficiency of the
company self service cafeteria, than by Ramac.
--
Grumpy Ol' Fred cisin(a)xenosoft.com
10 Jun
10 Jun
6:20 p.m.
On Jun 10, 2026, at 7:32 PM, Fred Cisin via cctalk
<cctalk(a)classiccmp.org> wrote:
Didn't show up on the list, so re-sending it:
---------- Forwarded message ----------
Date: Wed, 10 Jun 2026 12:14:39 -0700 (PDT)
From: Fred Cisin <cisin(a)xenosoft.com>
Subject: [cctalk] Ramac : The real first disk drive? (Was: Floppy disk
The first known and recognized disk drive of ANY type (hard disk preceded floppy) was the
Ramac, 70 years ago, 1956
https://www.computerhistory.org/storageengine/first-commercial-hard-disk-dr…
First one shipped was to Crown-Zellerbach Paper Company
CHM says June;
EDN and Google AI (Gemini) say September 13, 1956
https://www.edn.com/ibm-intros-1st-computer-disk-storage-unit-september-13-…
But, Gemini seems to also hallucinate RAMAC as being a company!
"At the 1958 Worlds Fair, RAMAC showcased its revolutionary random-access
capabilities by answering world history questions in 10 different languages."
(There was no Ramac Company exhibiting at the 1958 Worlds Fair)
Ramac had fifty 2 foot diameter double sided platters, and could hold a total of about
5MB. Modern drives can have even higher density!
I have a crashed Ramac platter, that I have made into a patio table, with the platter
under glass.
"Higher density" indeed. One of the first hard drives I used was 128 kB (DEC
RC11/RS64).
One peculiar aspect of the RAMAC is that it only had one head, or one pair, so track
switching was a lot slower than cylinder switching: it had to retract all the way, then
move the head vertically to the correct track, then seek in again to the right cylinder.
paul
6:50 p.m.
Did it have hydraulic positioners like the old CDC 3300 drives?
On Wed, Jun 10, 2026 at 6:29 PM Paul Koning via cctalk
<cctalk(a)classiccmp.org> wrote:
On Jun 10, 2026, at 7:32 PM, Fred Cisin via
cctalk <cctalk(a)classiccmp.org> wrote:
Didn't show up on the list, so re-sending it:
---------- Forwarded message ----------
Date: Wed, 10 Jun 2026 12:14:39 -0700 (PDT)
From: Fred Cisin <cisin(a)xenosoft.com>
Subject: [cctalk] Ramac : The real first disk drive? (Was: Floppy disk
The first known and recognized disk drive of ANY type (hard disk preceded floppy) was the
Ramac, 70 years ago, 1956
https://www.computerhistory.org/storageengine/first-commercial-hard-disk-dr…
First one shipped was to Crown-Zellerbach Paper Company
CHM says June;
EDN and Google AI (Gemini) say September 13, 1956
https://www.edn.com/ibm-intros-1st-computer-disk-storage-unit-september-13-…
But, Gemini seems to also hallucinate RAMAC as being a company!
"At the 1958 Worlds Fair, RAMAC showcased its revolutionary random-access
capabilities by answering world history questions in 10 different languages."
(There was no Ramac Company exhibiting at the 1958 Worlds Fair)
Ramac had fifty 2 foot diameter double sided platters, and could hold a total of about
5MB. Modern drives can have even higher density!
I have a crashed Ramac platter, that I have made into a patio table, with the platter
under glass.
"Higher density" indeed. One of the first hard drives I used was 128 kB (DEC
RC11/RS64).
One peculiar aspect of the RAMAC is that it only had one head, or one pair, so track
switching was a lot slower than cylinder switching: it had to retract all the way, then
move the head vertically to the correct track, then seek in again to the right cylinder.
paul
7:37 p.m.
"Higher density" indeed. One of the first
hard drives I used was 128 kB (DEC RC11/RS64).
Well, I said that it CAN have higher density, not quaranteeing that it
would :-)
The original 23FD was 80K
TLDR: long (too long) ramble about disk capacities:
8" SSSD (77 tracks * 26 SPT * 128 bytes poer sector) was 250K.
8" DSDD (77 tracks * 26 SPT * 256? bytes per sector) was about 1000 K
5.25" 500K data transfrer rate ("high density") was 2 sided 80 tracks per
side 15 secors per track of 512 bytes each),was 1200K, or 1.17M, NOT
1.2M unless you define meg as 2**10 * 10**3. instead of an honest 2**20
(1048576)
The earliest 5.25" (35 track SA400) had a capacity of 87.5K when formatted
with FM, ten sectors of 256 bytes each. (TRS80 and early Osborn).
other choices of size of sectors and number of sectors will vary that a
little.
But VERY soon they lengthened the slot for 40 tracks (100K)
GCR (Apple) gave an slmost 50% increase
But, FM double sided, then double density (MFM), and 96tpi for 80
cylinders (80 tracks per side)
MFM doubled the capacity (Higher density / more bits per track)
Going to 96tpi gave twice the total capacity, at 80 tracks per side, but
each track was the same as a 48tpi track.
Doubling the data transfer speed, was still MFM ("double density), but the
changed speed enabled almost twice as many bits per track
Yes, I know that later, there were barrium ferrite disks (E[xtended] D[ensity])
even some 192 track per inch, andsome bizarre ways to get a lot of data
onto a disk.
Changing a single sided format to double sided doubled the capacity, but
changing capacity is not the same as changing density.
One company (Intertec superbrain) insisted on calling the 340K double
sided version of its 170K single sided, "Double Density"!
Then when they went to 340K double sided, double density, they called that
"quad density"; everybody else in the world called it double sided double
density, and used "quad density" to refer to 640K - 800k 96tpi double
sided double density.
But then, when Superbrain went to 780K (which almost everybody else was
calling "quad density", Superbrain had already used up that name! So,
they called their 780K format, "SUPER Density"!
Then 3.5"
The Epson PF10 had 40 cylinders with 67.5 traxks per inch, but
everybody else immediately went to 135 tpi, giving it essentially the same
geometry visible to the computer as 5.25" double sided 96tpi.
One peculiar aspect of the RAMAC is that it only had
one head, or one pair, so track switching was a lot slower than cylinder switching: it had
to retract all the way, then move the head vertically to the correct track, then seek in
again to the right cylinder.
As opposed to ST225, with 4 heads for one platter. :-)
. . . or the Lisa Twiggy. :-) They claimed that the second thumb slot was
for the other heads, not just to make sure that all media would have
plenty of thumbprints.
Yes, switching to "side B" of a double sided disk was obviously much
quicker than stepping to another track.
--
Grumpy Ol' Fred cisin(a)xenosoft.com
7:43 p.m.
"RAMAC" is not the name of a disk drive!
RAMAC refers to a complete computer system that implements the "Random
Access Method of Accounting and Control", such as the IBM 305 RAMAC of
which the IBM 350 disk storage unit is a *component*.
So the name you're looking for is "IBM 350" which was the name of the first
disk drive.
7:55 p.m.
New subject: IBM 350 used in RAMAC : The real first disk drive? (Was: Floppy disk (fwd)
Yes, you are right.
Thank you
but, can I still say that crashed platter that I have came from a RAMAC
350?
Google AI (Gemini) has occasionally "thought" that Ramac was the name of
the company.
--
Grumpy Ol' Fred cisin(a)xenosoft.com
On Wed, 10 Jun 2026, Gavin Scott via cctalk wrote:
"RAMAC" is not the name of a disk drive!
RAMAC refers to a complete computer system that implements the "Random
Access Method of Accounting and Control", such as the IBM 305 RAMAC of
which the IBM 350 disk storage unit is a *component*.
So the name you're looking for is "IBM 350" which was the name of the first
disk drive.
9:04 p.m.
On Wed, Jun 10, 2026 at 10:44 PM Gavin Scott via cctalk
<cctalk(a)classiccmp.org> wrote:
RAMAC refers to a complete computer system that
implements the "Random
Access Method of Accounting and Control", such as the IBM 305 RAMAC of
which the IBM 350 disk storage unit is a *component*.
Back at one of my early jobs in the 80s, the owner told me a story
from when his dad worked at Columbus Coated Fabric (before they were
bought by Borden Chemical, the makers of Elmer's Glue). As the story
goes, CCF was either the first or second big company in Columbus to
buy a computer, an IBM 305 RAMAC, specifically for payroll. It was
then that I learned about one's-complement machines and 'negative
zero'.
-ethan
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participants (5)
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Ethan Dicks -
Fred Cisin -
Gavin Scott -
Jim Davis -
Paul Koning