The first hard drive, the RAMAC - Page 1
Forum section: electronics / general

author: Alex Eisenhut
author_rank: Super Contributor
timestamp: June 07, 2020, 10:04:52 am
content: I'm sure we've all heard of it or at least seen that picture of a RAMAC being hoisted on a cargo plane.But I never saw the IBM film about from the 1950s.Suddenly YouTube recommended this to me, the title doesn't make it very searchable.

author: Zbig
author_rank: Frequent Contributor
timestamp: June 07, 2020, 11:47:48 am
content: Wow, thank you. That was a fascinating watch for more than one reason. I find the style of these productions peculiar. The "penguin in a snow globe" scene was particularly deep

author: Tom45
author_rank: Frequent Contributor
timestamp: June 07, 2020, 02:20:50 pm
content: Thanks for that.That brings back memories. The local IBM office had a demo unit at one time. It was loaded with items about each day in history. You could specify a day and it would type out what happened on that day. I chose July 4, 1776. So it went back at least that far.A whopping 5 mega bytes of storage. What a deal.The film brought out what it was like to come up with something totally new from a blank sheet of paper. A totally different problem than just improving something that already exists.

author: Bill158
author_rank: Regular Contributor
timestamp: June 07, 2020, 08:21:59 pm
content: Thanks also for interesting video.At around 4:40 into the video did you see what appears to be a TEK plugin for a 500 series scope on the desk? I wonder why it was sitting there? No scope to be seen anywhere around them at that time, but later on in the video there were 500 series scopes. But exactly when was the first 500 series plugin scope manufactured by TEK?In looking at catalogs it looks like the first ones were the 531 and 535 in the August 1954 catalog.Bill

author: aqarwaen
author_rank: Regular Contributor
timestamp: June 07, 2020, 09:04:07 pm
content: how long it would taken to write all 5mb space?and how fast write and read speed was approx?

author: Alex Eisenhut
author_rank: Super Contributor
timestamp: June 08, 2020, 01:03:19 am
content: Quote from: aqarwaen on June 07, 2020, 09:04:07 pmI don't really know, check the wiki article. For one thing it doesn't record 8-bit bytes, it uses 6-bit characters, and for another I suppose the actual speed is dominated by the seek time of writing to so many platters. It is only one head assembly flying around all those platters!Wiki says "Data transfer rate is 8,800 characters per second" so maybe 8 minutes at best, add in the time it takes to move that head around, maybe in 10 minutes you can fill it up.This thing was still a lot faster than the 1541 disk drive I had growing up. So for the late 1950s when all you had was payroll and inventory it was very fast.

author: duak
author_rank: Super Contributor
timestamp: June 08, 2020, 03:55:51 am
content: Here's another one, about 10 years later:I have a Honeywell disk drive (in pieces) using about the same vintage technology. I got it in the late 70s after it was pulled from a data center. It came with a pack and if memory serves, it stored about 16 Mbytes. I think the bit rate was 1 or 2 MHz because the formatter that came with it had a crystal with that frequency. I spooled it up, loaded the heads and was able to see the data after the read amps with a scope but never went further. Within a very few years winchester drives became cheap so I repurposed the old Honeywell and used the drive motor for a bench grinder. The frame was strong like tractor and had casters so I made a mobile bench that now holds a milling machine. I took the disk pack apart and found that two or three surfaces had their oxide layers taken off from crashes. The head actuator was hydraulic so there was a little hydraulic pump driven off the motor. The whole lower part of the drive containing the motor, cardcage and cabling had a coating of oil. Apparently, the flat drive belt could slide off the pullies and if the heads weren't near the outer edge, they would land and remove the oxide from the platters.The spindle bearings in these things are quite high quality. I've been thinking of repurposing it as a grinder or maybe a centrifuge or spin coater. Hmm, I have a lathe in pieces, maybe I could transplant it if it has the load capacity.