At 02:35 PM 9/16/2006, CRC wrote:
>The basic problem with commercial CD burners/players is that they
>keep the laser diodes on when powered, although at the low power
>required for reading. The life of run-of-the-mill laser diodes is on
>the order of 10,000 (10.000) hours. Consequently, if you keep your
>system on all the time you can expect one to two years of useful life
>from the beast (some longer, some shorter). From <http://www.wtec.org/ loyola/opto/ad_rohm.htm>:
That document dates from 1994. You'd think that manufacturers would
want to increase MTBF and eliminate failures as quickly as possible,
so I find it hard to believe that LEDs are left on inside today's
CD/DVDs just because it's hard to turn them off and they don't want
to improve lifetimes. This info may be entirely relevant for
1980s drives, who knows? What sorts of other ancedotes and
claimed facts do we have?
From the CD-R FAQ: http://www.cdrfaq.org/faq05.html
Subject: [5-2] How long do CD recorders last? (1998/04/06)
The MTBF (Mean Time Between Failures) on these drives is typically 50,000
to 100,000 hours, and they come with a 1 year warranty. Compare that to
hard drives rated at between 500,000 and 1,000,000 hours with a 3 or 5
year warranty and that should give you some idea. Most of the drives
available today weren't meant for mass production of CD-Rs. The only
exceptions are the venerable Philips CDD 522, Kodak PCD 600, and Sony CDW-900E.
By 2004, MTBF for consumer CD/DVD were up to 60K to 100K hours:
http://www.computingondemand.com/reviews/storage-LiteOn-LDW-411S/page1.shtml
And perhaps their MTBF was calculated with a 2% duty cycle, which
would still mean they expect a consumer DVD-R to be able to burn
several thousand discs. I suspect consumer losses are due more to
dust and crud on discs... unless of course you simply don't want to
trust manufacturer-provided MTBFs.
Your average $50 Wal-Mart DVD drive has a 70K MTBF:
http://www.liteon.com/prod/getProduct.do?cid=1_7_13&xml_id=4_2&menu_id=4_2_7
- John
Hi,
I got some 68000 DIP chips for ?3.00 off of www.vintagecomputermarketplace.com the other week. I finally
got around to checking that they are of use to me (
by comparing them with notes I have on the internals
of my old A600 Rev 1.1) and discovered that they ma
y not be of use to me! :(
Here's the low-down on them:
MC68000P10
2 C91E DIP chip (rectangle with pins on l
ong sides) x 2
QEDB9215
S (large logo S) SCN68000CAN64
2208N19 DIP chip x1
9035KE
Any idea's what computer they are from/for?
Regards,
Andrew B
aliensrcooluk at yahoo.co.uk
Does anyone have a copy of the HP 64516A PROM Programmer Module manual?
This is for the 27512 chip bucket, not the main control card. I'd like to
build one of these, so I'm specifically looking for the schematic and parts
list from the manual. Thanks.
-- Dave
4D/35 has a seperate fan on the compute side to cool the 35 MHz R3000.
I have a 4D/25 that a prior owner let choke with dust and the heat ate the R3010 and
the RE2 on the graphics side, cooling is definitely an issue on these beasts.
Is it Express or Eclipse graphics? Express will have the stereo connector.
If eclipse, is it Turbo or normal?
Josh, did you get my offlist E-mail?
How many Amps should the fuse in the C64 be rated for? The fuse I
pulled is a 1.5A 250V fuse, yet "Troubleshooting & Repairing your
Commodore 64" says to use a 1A 250V fuse. A quick bit of googling
seems to indicate that it should be 1.5A.
Zane
--
| Zane H. Healy | UNIX Systems Administrator |
| healyzh at aracnet.com (primary) | OpenVMS Enthusiast |
| MONK::HEALYZH (DECnet) | Classic Computer Collector |
+----------------------------------+----------------------------+
| Empire of the Petal Throne and Traveller Role Playing, |
| PDP-10 Emulation and Zane's Computer Museum. |
| http://www.aracnet.com/~healyzh/ |
How does one bolt one DEC corporate cabinet (RK07-PA/H9642) to another
corporate cabinet (H9612-AA)?
The H9612 has the removable black area of the side panel, so I was able to
put them next to each other and it looks seamless.
How does one attach them with hardware, and what do I need?
Thanks
Julian
>
>Subject: Re: CompuPro floppy controller differences
> From: Fred Cisin <cisin at xenosoft.com>
> Date: Mon, 18 Sep 2006 11:43:10 -0700 (PDT)
> To: "General Discussion: On-Topic and Off-Topic Posts" <cctalk at classiccmp.org>
>
>> Many can. The original IBM PC version was a an abortion.
>
>It was way worse than that.
>Calling it "an abortion" is an affront to those who are Pro-Choice.
>
I always miss that association.. But maybe the words atrocity, fubar
and low grade hack get closer to how I feel.
Never did feel the PC was good design, though I've held it up
as an example of a bad design made to work passibly.
Allison
At 07:04 AM 9/18/2006, you wrote:
>Does anyone know if this is a real working PDP-1 or a mocked up, emulated
>thingy?
>Might be interesting for the games nostalgia for those (like me) whose
>classic computing interest overlaps to classic gaming.
>http://www.sciencemuseum.org.uk/exhibitions/gameon/
This exhibition was in Chicago at the Museum of Science and Industry
two years ago. Looked like a real PDP-1 to me. I took pictures
and I thought I posted something to this list about my visit,
but I can't find it now. It was interesting for the kids and I,
for me if only for the experience of seeing an Amiga under glass in a
museum exhibit. :-)
- John
Does anyone know what sort of interface the AT&T 3b2 uses for its mouse?
I found one which is missing its mouse.
--
David Griffith
dgriffi at cs.csubak.edu
A: Because it fouls the order in which people normally read text.
Q: Why is top-posting such a bad thing?
A: Top-posting.
Q: What is the most annoying thing in e-mail?