"Short Wave Sportfishing" wrote in message
...
On Tue, 4 Dec 2007 08:29:22 -0500, "Eisboch" wrote:

http://www.neatorama.com/images/2006...puter-1956.jpg

In September 1956 IBM launched the 305 RAMAC, the first computer with a
hard
disk drive(HDD). The HDD weighed over a ton and stored 5MB of data.

That's not a typo ..... 5MB of data.

If I remember correctly, the ones that DEC and DG built used head
motors that weighed 160 pounds and were made out of cast aluminum.

Damned things were bigger than washing macines.

Motors were not that heavy. But the voice coil magnets were about 15
pounds. Still have a couple of them stuck to the side of the tool chest.

wrote:
On Wed, 05 Dec 2007 02:50:25 GMT, Short Wave Sportfishing
wrote:

On Tue, 4 Dec 2007 08:29:22 -0500, "Eisboch" wrote:

http://www.neatorama.com/images/2006...puter-1956.jpg

In September 1956 IBM launched the 305 RAMAC, the first computer with a hard
disk drive(HDD). The HDD weighed over a ton and stored 5MB of data.

That's not a typo ..... 5MB of data.
If I remember correctly, the ones that DEC and DG built used head
motors that weighed 160 pounds and were made out of cast aluminum.

Damned things were bigger than washing macines.


I still have one of the multi-platter disk packs for my old CDC 300 megabyte
"washtub". The pack alone weighs about 40 or 50 pounds. The matching 300
megabyte winchester drives in the PDP11's took two people to install. One to
power lift the drive, and a second to guide it onto the rails.

The CDC required head re-alignment of all of those heads every few months. It
was quite a chore.

Head crashes then are today's operation.

I remember the screech of 2314's and 3330's when the heads crashed and
then the crying of the operators. Not a pretty sight.

Today the heads rid on the disks. Amazing!

"Eisboch" wrote in message
...

wrote in message
...
On Tue, 4 Dec 2007 17:09:22 -0500, "D.Duck" wrote:

The IBM 350 disk system stored 5 million 8-bit (7-bits plus 1 odd parity
bit) characters (about 4.4 MB).

http://en.wikipedia.org/wiki/IBM_305


Somebody needs to fix the Wiki.
It was 7 bits (remember the "odd parity"?)
The bits are 1, 2, 4, 6, A, B and parity.
It goes with "7 track tape" etc.

The most popular military teletype machines (Mod 28 ASR33) were 7 bit
ASCI with an 8th parity or "stop" bit.

Eisboch

Eisboch

Model 28 is 5 bit and Model 33 is 8 bit.

In the 8 bit ASCII code the 8th bit is the parity bit. The stop bit is
usually two bits in length and was in incorporated to help "synchronize" the
sending and receiving terminals.

On Dec 4, 9:23 pm, Short Wave Sportfishing wrote:
On Tue, 04 Dec 2007 20:22:06 -0500, Wayne.B





wrote:
On Tue, 04 Dec 2007 23:13:55 GMT, Short Wave Sportfishing
wrote:

My first computer had a paper tape reader and I had to cold start boot
strap it.

The first computer I ever programmed was like that:

Summer of 1967, Control Data 160A, 4K 12 bit words, as big as a large
desk, cost approx $80K, paper tape in, paper tape out, environmental
requirements: 72 degrees F +/- 2 degrees, 50% humidity +/- 10%. We
copied the cold boot tape onto metalic mylar to keep it from wearing
out quite as fast.

Bear in mind that $80K then was like $500K now. Surprisingly enough
we actually got some useful work out of the machine and I launched my
entire adult career with it.

Technically, I suppose my first "personal" compuer was an original
Roberts calculator kit. One of the AF Captains in the survival course
at Kessler knew him and we got to talking and he obtained one for me.

Pretty cool deal. Next up was an Altair 8800 when I went to work for
DG - basically the front panel was a duplicate of the original Nova
computer.

I know I've told the story about programming the computer at Sylvania
with phone jacks.- Hide quoted text -

- Show quoted text -

I remember my brother was going to school and bought a calculator for
his electronics and math courses. It was a TI and he payed something
like $150 for it. I thought it was amazing because it would do square
roots! Of course, it took him a long time to trust it, he'd check it
with his slide rule. I learned to use his slide rule while I was in
high school, never forgot, although by the time I got to college,
calculators had come a long way, although I will never forget the day
I got my first HP 48G.

wrote in message
...
On Tue, 4 Dec 2007 23:27:19 -0500, "Eisboch" wrote:


wrote in message
. ..
On Tue, 4 Dec 2007 17:09:22 -0500, "D.Duck" wrote:

The IBM 350 disk system stored 5 million 8-bit (7-bits plus 1 odd parity
bit) characters (about 4.4 MB).

http://en.wikipedia.org/wiki/IBM_305


Somebody needs to fix the Wiki.
It was 7 bits (remember the "odd parity"?)
The bits are 1, 2, 4, 6, A, B and parity.
It goes with "7 track tape" etc.

The most popular military teletype machines (Mod 28 ASR33) were 7 bit
ASCI
with an 8th parity or "stop" bit.

Eisboch

Eisboch


This wasn't ASCII, it was Binary Coded Decimal. The problem with even
parity is a "blank" is even. All IBM machines used some varient of BCD
before the 360 and "hex"
That was a typo above bits are 1, 2, 4, 8, A, B parity.

Maybe you're right ... it's been a long time. I seem to remember though
being taught that the military teletype machines that I worked on were 100
wpm (or maybe it was 110 wpm), 8 bit ASCII. Several machines would be
running in the radio shack copying several channels of an multiplexed fleet
broadcast.

I used to have a manual that I "borrowed" but I haven't seen it in years. I
*do* have a little card that the Navy awarded you when you graduated from
the school in Norfolk. It has your name, date, and confers the title of
"Doctor of Teletype Technology". :-)

I am probably wrong, but that's what I remember.

Eisboch

wrote in message
...
On Tue, 4 Dec 2007 23:27:19 -0500, "Eisboch" wrote:


wrote in message
. ..
On Tue, 4 Dec 2007 17:09:22 -0500, "D.Duck" wrote:

The IBM 350 disk system stored 5 million 8-bit (7-bits plus 1 odd parity
bit) characters (about 4.4 MB).

http://en.wikipedia.org/wiki/IBM_305


Somebody needs to fix the Wiki.
It was 7 bits (remember the "odd parity"?)
The bits are 1, 2, 4, 6, A, B and parity.
It goes with "7 track tape" etc.

The most popular military teletype machines (Mod 28 ASR33) were 7 bit
ASCI
with an 8th parity or "stop" bit.

Eisboch

Eisboch


This wasn't ASCII, it was Binary Coded Decimal. The problem with even
parity is a "blank" is even. All IBM machines used some varient of BCD
before the 360 and "hex"
That was a typo above bits are 1, 2, 4, 8, A, B parity.

I think the confusion here is comparing the Teletype machines and the IBM
machine. The Teletype Model 28 is 5 bit baudot and the Teletype Model 33/35
is 8 bit ASCII.

On Wed, 5 Dec 2007 08:52:20 -0500, "D.Duck" wrote:

I think the confusion here is comparing the Teletype machines and the IBM
machine. The Teletype Model 28 is 5 bit baudot and the Teletype Model 33/35
is 8 bit ASCII.

That's my recollection also. The model 28s used a "mode shift" key or
some such to effectively double the character set. If the "mode
shift" code arrived garbled, the receiving machine would miss
everything that followed and print gibberish.

"Wayne.B" wrote in message
...
On Wed, 5 Dec 2007 08:52:20 -0500, "D.Duck" wrote:

I think the confusion here is comparing the Teletype machines and the IBM
machine. The Teletype Model 28 is 5 bit baudot and the Teletype Model
33/35
is 8 bit ASCII.

That's my recollection also. The model 28s used a "mode shift" key or
some such to effectively double the character set. If the "mode
shift" code arrived garbled, the receiving machine would miss
everything that followed and print gibberish.


For such a mechanical contraption, they were amazing.

http://video.google.com/videoplay?do...544&q=mod-tage

Eisboch

"Eisboch" wrote in message
...

"Wayne.B" wrote in message
...
On Wed, 5 Dec 2007 08:52:20 -0500, "D.Duck" wrote:

I think the confusion here is comparing the Teletype machines and the IBM
machine. The Teletype Model 28 is 5 bit baudot and the Teletype Model
33/35
is 8 bit ASCII.

That's my recollection also. The model 28s used a "mode shift" key or
some such to effectively double the character set. If the "mode
shift" code arrived garbled, the receiving machine would miss
everything that followed and print gibberish.


For such a mechanical contraption, they were amazing.

http://video.google.com/videoplay?do...544&q=mod-tage

Eisboch


Still remember the first KSR-33 I ever saw. Was working in the Western
Electric Warehouse when the forklift operator got a pallet with one off the
top of the storage racks. Someone had not strapped down the unit, and the
top of the rack must have been 25' in the air. That KSR33 nosedived to the
floor and parts went everywhere. Later when I had to work on the Teletype
that NCR used as the console writer on the later Century systems, I wanted
to drop more of them 25'. They used the light duty model, forget the
number, that was designed to receive 3-4 messages a day and only turned on
when a message came in. NCR ran them 24/7 and the shafts eventually were
cut almost in half by the oillite busings wearing out.

"Calif Bill" wrote in message
...

"Eisboch" wrote in message
...

"Wayne.B" wrote in message
...
On Wed, 5 Dec 2007 08:52:20 -0500, "D.Duck" wrote:

I think the confusion here is comparing the Teletype machines and the
IBM
machine. The Teletype Model 28 is 5 bit baudot and the Teletype Model
33/35
is 8 bit ASCII.

That's my recollection also. The model 28s used a "mode shift" key or
some such to effectively double the character set. If the "mode
shift" code arrived garbled, the receiving machine would miss
everything that followed and print gibberish.


For such a mechanical contraption, they were amazing.

http://video.google.com/videoplay?do...544&q=mod-tage

Eisboch


Still remember the first KSR-33 I ever saw. Was working in the Western
Electric Warehouse when the forklift operator got a pallet with one off
the top of the storage racks. Someone had not strapped down the unit, and
the top of the rack must have been 25' in the air. That KSR33 nosedived
to the floor and parts went everywhere. Later when I had to work on the
Teletype that NCR used as the console writer on the later Century systems,
I wanted to drop more of them 25'. They used the light duty model, forget
the number, that was designed to receive 3-4 messages a day and only
turned on when a message came in. NCR ran them 24/7 and the shafts
eventually were cut almost in half by the oillite busings wearing out.


That 300 Megabyte DEC drive the RM05 was a CDC build drive. The RM03 was a
smaller version. When I was an engineer for System Industries we sold the
drive as a CDC 300 MB drive and disk controllers that looked just like the
DEC controllers software wise. Plus we could hook several systems up to the
same controller for shared data.