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SuperHero

Joined: 10 Dec 2003 Location: Superhero Hideout
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Posted: Tue Dec 04, 2007 5:16 am Post subject: 5MB HDD weighs 1 ton |
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5MB HDD weighs 1 ton
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The 350 Disk Storage Unit consisted of the magnetic disk memory unit with its access mechanism, the electronic and pneumatic controls for the access mechanism, and a small air compressor. Assembled with covers, the 350 was 60 inches long, 68 inches high and 29 inches deep. It was configured with 50 magnetic disks containing 50,000 sectors, each of which held 100 alphanumeric characters, for a capacity of 5 million characters.
Disks rotated at 1,200 rpm, tracks (20 to the inch) were recorded at up to 100 bits per inch, and typical head-to-disk spacing was 800 microinches. The execution of a "seek" instruction positioned a read-write head to the track that contained the desired sector and selected the sector for a later read or write operation. Seek time averaged about 600 milliseconds.
With storage capacities of 5 million and 10 million digits, and the capability to be installed either singly or in pairs, the 350 provided the 305 system with storage capacities of 5, 10, 15 or 20 million characters.
An IBM RAMAC 305 with a 350 disk storage unit leased for about $3,200 per month back in 1957. Over a thousand of the 305 systems (one of IBM's last vacuum tube units) were manufactured before production ended in 1961, and the 305 was withdrawn in 1969. |
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mindmetoo
Joined: 02 Feb 2004
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Posted: Tue Dec 04, 2007 3:12 pm Post subject: |
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The first computer I used with a HD the HD held about 5 mb. It was basically about the size of a small round suitcase encasing about 8 serving plate sized disks. The advantage to these HDs besides portability was they could be swapped. |
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eamo

Joined: 08 Mar 2003 Location: Shepherd's Bush, 1964.
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Posted: Tue Dec 04, 2007 4:41 pm Post subject: |
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It's hard to imagine all that machinery in the 60's-70's was actually worth its while. Just think how buggy they must have been and how much maintenance they must have needed.
I've always thought the revolution in office equipment at that time was the photocopier or the electronic printer. Not the computer. |
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mindmetoo
Joined: 02 Feb 2004
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Posted: Tue Dec 04, 2007 8:21 pm Post subject: |
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eamo wrote: |
It's hard to imagine all that machinery in the 60's-70's was actually worth its while. Just think how buggy they must have been and how much maintenance they must have needed.
I've always thought the revolution in office equipment at that time was the photocopier or the electronic printer. Not the computer. |
It's a bit like thinking "why did they fight with muskets when they could have just fielded crossbow men or Welsh longbow men". Even back then computers were certainly useful. That you could dump in some punch cards and get it to calculate things that would take a room full of people a month to do was amazing. |
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itaewonguy

Joined: 25 Mar 2003
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Posted: Tue Dec 04, 2007 8:58 pm Post subject: |
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I remember walking into IBM and toshiba stores in the early 90's and my friend and I going
WOW!!! 2 gig laptops!!! I would so love to own that!!
hahahahahahaha 2 gigs??? hahahaahahahahaa what was I on!!!
still that was the chit back then!! |
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OneWayTraffic
Joined: 14 Mar 2005
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Posted: Tue Dec 04, 2007 9:10 pm Post subject: |
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It's all relative. The Apollo computer was powerful enough to go to the moon, though it'd make a nice (low end) pocket calculator today. Even the earliest computers were very useful. I grew up with the Amiga so I still think of the original M68000 as a benchmark in power. In my opinion that was the first powerful home use chip and everything since then is just- more powerful.
Anyone else notice the seek speed on that drive? 600ms. A modern drive is about 10 times faster. So though everything else has grown exponentially seek speed hasn't. |
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The King of Kwangju

Joined: 10 Feb 2003 Location: New York City
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Posted: Wed Dec 05, 2007 3:21 pm Post subject: |
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The company I work for used to have 20 locations in Toronto. They had a fleet of cars and drivers and their job was to drive contracts and paperwork around the city from location to location.
They tell me the story of when the fax machine was invented. It was a shame that all those nice men lost their jobs, and there were no more free rides downtown, but the documents sure got around a lot quicker. |
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Leonidas

Joined: 24 Nov 2007
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Posted: Wed Dec 05, 2007 5:07 pm Post subject: |
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The King of Kwangju wrote: |
They tell me the story of when the fax machine was invented. It was a shame that all those nice men lost their jobs, and there were no more free rides downtown, but the documents sure got around a lot quicker. |
They had cars in 1843? The fax was invented then -even before the telephone, but I don't think cars were. I guess you mean when fax machines became common and affordable. |
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mindmetoo
Joined: 02 Feb 2004
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Posted: Wed Dec 05, 2007 8:53 pm Post subject: |
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Leonidas wrote: |
The King of Kwangju wrote: |
They tell me the story of when the fax machine was invented. It was a shame that all those nice men lost their jobs, and there were no more free rides downtown, but the documents sure got around a lot quicker. |
They had cars in 1843? The fax was invented then -even before the telephone, but I don't think cars were. I guess you mean when fax machines became common and affordable. |
There's an initial invention and then there's the invention of a commercially usable device. |
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The King of Kwangju

Joined: 10 Feb 2003 Location: New York City
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Posted: Thu Dec 06, 2007 7:58 am Post subject: |
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Leonidas wrote: |
I guess you mean when fax machines became common and affordable. |
Yes, that's probably what I meant.
They also tell me the story about the first mac they bought for the shop, so they could lay out their internal newsletter. It saved them the cost of hiring a designer, but the mac was $16,000. |
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