Talk:Quantum Corp.

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Contents 1 About the notes 2 The Optical System 3 What to do about the notes 4 Manufacturing in Ireland 5 Updating Quantum Article

[edit] About the notes

Those notes at the bottom are a great addition. Hydrargyrum, if you come back by this page, can you see if there's any details I missed? I wrote most of this article, based on having read Quantum's patents and doing research in old magazines and the New York Times, and I'm wondering if there's any other inside information that would be useful. (Oh, and did the Shrewsbury designs continue using a 68k processor even after the Quantum takeover? I remember taking apart an old DSP series drive and seeing a 68030 in it, and I know the Milpitas designs more or less universally used NEC 78k CPUs.) -lee 14:48, 11 April 2006 (UTC)

To add to this, it looks like we've had a visit from someone in Shrewsbury...[1] -lee 23:44, 12 May 2006 (UTC)

hahahahahahahahaha —Preceding unsigned comment added by 66.191.242.231 (talk • contribs)

Nice try. That geolocation tool is getting confused becuase it would seem Maxtor has all its internal IPs in a netblock issued out of Longmont. If you do a traceroute, the route goes through Boston. -lee 01:48, 2 June 2006 (UTC)

[edit] The Optical System

A couple of comments regarding the Quantum optical system discussed in the "Origins" section...

 

"they put a diffraction grating on the head arm"

It wasn't a diffraction grating, at least they didn't intend it to be one! Quantum referred to that part in their documentation as a "glass scale", and it was attached to the actuator arm, which moved the head (and thus the scale) back and forth across the disk surface.

The scale was a small, light, very thin piece of glass whose surface had an array of narrow chromium plated lines separated by equal widths of clear glass. The pitch of the lines matched the track pitch on the disk.

Immediately below the scale was a glass reticle, under which was a matching quad photo detector array. The reticle had four openings, one above each cell of the photo array, and each opening was plated with a pattern of lines that matched those on the scale. The phase relationship between the lines in each of the four windows (relative to the scale) was 0°, 90º, 180º and 270º. This allowed for quadrature detection of exact track position and direction of head movement.

The optical system also contained an IR LED that sent light through the scale then through the reticle, to be detected on the quad photo detector. During a seek the system merely needed to count the number of track crossings seen by the detector array to know when it was approaching the desired track. And to then use the quadrature data to place and maintain the head precisely on that track.

 

"the optical system was deemed too slow to be competitive and was discontinued"

Actually, that is not quite accurate. As originally introduced, the optical servo system was an elegant and cost-effective solution. However, as track densities increased, and consequently the line pitch on the scale increased, there came a point where the "scale" had indeed turned into a diffraction grating!!!

The Quantum optical system relied on the light acting as if you were drawing it in a ray tracing program and not as a true electro-magnetic wave function that could "bend" around sharp corners. As soon as the diffracted light became a significant percentage of the light going through the scale, the system lost its ability to accurately seek and follow a track.

By the time of the demise of the optical system, track pitch (and thus line pitch on the scale) was 13um, while the wavelength of the IR emitter was a mere 0.9um. Even though the IR wavelength was more than an order of magnitude smaller than the scale openings, still, about half the light energy was being strongly diffracted. That was the limit the Quantum optical system could stand.

In other words, the optical system died because of snowballing track density requirements. (Although, if it had not been for the diffraction problems, it's true that speed would have eventually caught up to and killed Quantum's optical system.) The diffraction problem was not the only design problem the optical system faced, but it was the one that dealt it the death blow.

The last Quantum drives using the optical system were the Gemini series of drives. Even then, the parts cost for the entire optical system was about $5.25!

I have no idea how useful the above information is to the principle author of the Quantum article, but feel free to use as much or as little of it as you see fit. I'm quite confident there is nothing I wrote above that is any longer proprietary.

Boot 07:58, 25 May 2007 (UTC)

Thanks for the extra information on this. You're right; I did fudge a few things in the original article, since I was working from memory and back in 2003 or so, Wikipedia was still pretty lax about citing sources. If I goofed on something, feel free to go ahead and change it. (Also, I should note that what I know about these drives came mainly from Quantum's patents, some of which are very nearly full technical manuals, and from actually taking a few drives apart. I've never actually worked for Quantum or any of their successors, I just had something of an obsession with their drives back in the 1990s -- mainly fueled by glowing reviews in MacUser, of all things -- and had to know what made them tick. :D)

PS. I actually do have a Gemini here (the LPS120AT, to be specific), and it still works fine with no bad sectors despite being 16 years old. It's not of much use in an era where they practically put 1GB USB keys in cereal boxes, but it's still impressive. -lee 23:56, 25 May 2007 (UTC)

Thanks for your response, Lee. The observations I made above were minor and hyper-technical in nature, so I'll only add a note to the main article to click on the discussion page for more detail.

One extra technical note, the Quantum optical servo system was the brain child of their head of Advanced R&D, Bill Moon, a certifiable genius and a real kind gentleman, to boot.

I got a kick out of your comment about how you learned about the drives through disassembling them, that's the mark of a very healthy mind! I learned from spending four years at Quantum as an engineer.

About those "glowing reviews in MacUser" that you mention, Apple was easily Quantum's single biggest HDD customer for almost the entire time Quantum was in the HDD business. Boot 00:19, 26 May 2007 (UTC)

Ah yes, Apple OEM drives. Those were fun. The oldest Apple OEM drive I've run into so far was a mid-1980s Q280 (most likely a pull from a Mac II!) that, sadly, no longer worked when I got it (it'd either been dropped hard or degaussed). I've also seen some Apple OEM drives that were, to put it mildly, VERY weird. A few machines in the late 1980s/early 1990s had those oddball Sony drives in them (AFAIK the only hard drive Sony ever made) -- I think Quantum actually sued Sony over that, since the optical servo system was in them). There was also the MiniScribe 20MB that was in the SE, but MiniScribe was always strange. (I also hear tell the people that designed Conner's first drives were ex-MiniScribe, which explains a lot.)

And yeah, Bill Moon, I know about him. His name's all over Quantum's early patents. He sounds like he would have been an interesting guy to meet. 66.93.100.114 03:42, 26 May 2007 (UTC)

Oh, oops, that was me; I forgot to log in. -lee 03:44, 26 May 2007 (UTC)

I moved the discussion of the optical feature into a separate section. Much of the text here was useful! I hope it makes sense. -- Austin Murphy 18:29, 27 August 2007 (UTC)

[edit] What to do about the notes

I have some problems with the Notes section in this article:

• It might be getting long. We're up to 7 footnotes now, and it's starting to look messy.
• Parts of it read like an advertisement. Ever since Shrewsbury passed by, it's read like a pep rally for their team, complete with boasting about how Storage Review likes their drive (which is well and good, but not terribly encyclopedic) and how great things are going to be under Seagate (noting, of course, that Seagate doesn't even mention the Atlas 15k on their site now). I propose trimming out the bits that read like that, and possibly removing the bits about their little turf war with Milpitas unless someone else (Boot Hill, Quicksilver?) can add more about it.
• Reliable sources. All of this is based on primary sources and anecdotes from people that were there. I really wish we had a better way of vetting all this, but no one's written a book about it yet...

Comments? -lee 11:51, 11 June 2007 (UTC)

I agree that the notes are taking over the page, but I think they hold the best parts of the article. My opinion is that they should be rolled into the main article. We can probably tone down the "rah-rah" part. Some of it may make more sense in the Seagate article or even a DEC Storage article. Primary sources are not a problem as long as they are identified. Why not make a little primary sources section on this talk page? -- Austin Murphy 19:07, 11 June 2007 (UTC)

Hmm. That may not be so bad, then. -lee 04:16, 27 June 2007 (UTC)

I deleted the notes after moving a lot of the info into the article. It could still be improved a lot, but I think this is an improvement. -- Austin Murphy 18:21, 27 August 2007 (UTC)

It looks a lot better than it did. Thanks for the help! -lee 14:15, 30 August 2007 (UTC)

[edit] Manufacturing in Ireland

I think I recall some Quantum hard disks from the mid-90s allegedly being made in Ireland. this article also suggests that they have or had some operation in Dundalk. Anyone have any more info? --Zilog Jones 21:45, 12 June 2007 (UTC)

This is totally anecdotal, but I had one of the Ireland-made disks some time ago (I forget now which exact model it was, but it was form the ST/SE era, about 1997.) -lee 04:17, 27 June 2007 (UTC)

I think it was just a repair facility and a warehouse. The articles I can find are kind of vague. It appears that production is currently in Panang, Malaysia. -- Austin Murphy 16:51, 27 August 2007 (UTC)

[edit] Updating Quantum Article

Hi, I work at Quantum and noticed the description at the beginning of the article is out of date. I thought it would help to add some of the technologies Quantum is currently offering. I may also be able to add some historical perspective having originally joined back in 2000.

More than just tape drives, Quantum also sells tape library, disk-based virtual tape library or VTL systems, data de-duplication technology, and storage management software.

Let me know if I can help with any specific verifications and I may be able to find source materials (as long as it is not company confidential or copyrighted material).

Slamby (talk) 00:08, 16 January 2008 (UTC)