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When Spun Really Fast, CDs Explode
Anonymous Coward writes: "Ever wonder why cd-rom/cd-rw drives are not getting any faster? Wonder why they heat up? This page has a rather amusing experiment where they put various CD's into something that can spin up to 30,000RPM and found that most cd's explode at just around 28,000RPM. Oh and they seem to like using Corel CD-ROM discs for their experiment." Update: Yep, it's a dupe...
Going to go ahead and be redundant and say that I saw this story somewhere else not too long ago... ...Oh yeah, it was here!
Appended to the end of comments you post. 120 chars.
Instead of the moderators modding this offtopic they should have modded it Intelligent. Maybe if the moderators knew how to use the search engine we wouldn't have this problem. Or maybe Slashdot is just like normal news venues and just recycle material.
OK. The staff can't be perfect, but this is not even close to being all that unique. I remember this story as well.
I suggest the department headings be changed from frivolous titles to useful ones, to help with categorisation. I'd also like to see duplication URLs recorded, as Sircus suggests.
Someone here noted that Slashdot has an option to show all sections. Perhaps editors should have this as a mandatory condition on their own logged-in sessions.
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Death will come, and will have your eyes
-- Pavese
will be one of two things I think:
1. The CD will be spun at 64x or so clockwise. Under that will be a second counter-rotating plane that will contain the laser. With the platters rotating in opposite directions you can break the 30K RPM physical limitations of the media. You can build the mechanism strong enough to do 300x normal CD speed I'd guess. 300 * 64 = 6,000x or ( 2.5GB/s). I wouldn't be surprised to start seeing such a mechanism in hard drives either. The disks i
2. What I think will truely be the big breakthrough will be to not spin the disk or reader mechanism at all. Instead, the drive will use a scanner like method to read the entire CD in to a 700MB buffer in a few seconds. The disk will then sit idle while all requests are served from the buffer. I see this used in a slot loading scheme, so as the disk is drawn in it is read.
The nifty thing about this would be that you could create a CD image in the buffer, change the bugger copy just like a normal disk drive, then eject the physical master and burn the buffer to a new CDR(/CDRW disk.
Article X: The powers not delegated... by the Constitution...are reserved...to the people
The "ring" could work much like a phone cord detangler - bars at extend each to a different ring. The other problems you have here:
Synchronization: Getting the laser at one spot on a CD is a complex process (so much so that a buffer underrun can cause a misalignment in a burnt CD, making coasters). If you spin the CD and the laser at different variable speeds, you would need some great hardware calculating that would be able to put the two speeds to gather as they vary.
Communication: Getting power is pretty easy, but what about returning data? You could use the same spinning wire-on-ring system, but I think it would limit the communications bandwidth.
I think a better system would be to have 2+ read heads on a CD-ROM. Two or four read heads could more quickly access data if they were fully independant. Drive access time could be halved, as could seek time. Two heads could "stripe" data, allowing the transfers to be even faster.
Well, I'll stop.
That what was all this school was for... to teach us how to solve our own problems. -- janeowit
It's not the moderators, it's the editors...
Which makes one wonder what the hell we need them for if they can't edit a damned thing anyway...
The GPL makes software more like your mom. Free and open to all.
I'm so sorry for interrupting the rivetting and intellectual conversation on blowing the shit out of CDs.
Get back to me(in another thread, I give up here, the "nuke this thread" defense is almost as hard to counter as the chewbacca defense) when your mind learns that a straight line is not always the most productive way to reach point C from point A(ie. life, like this conversation, is full of interesting detours, don't shut them out just because it strays from the path).
Being a pseudo-intellectual is fun!
It's been a long time.