test-drb September 2006

test-drb@ccmp.vtda.org

200 participants
374 discussions

FW: Third round of Diskette Experiments completed (results)

by ajp166＠bellatlantic.net

> >Subject: Re: FW: Third round of Diskette Experiments completed (results) > From: ard at p850ug1.demon.co.uk (Tony Duell) > Date: Thu, 28 Sep 2006 23:39:28 +0100 (BST) > To: cctalk at classiccmp.org > >[...] > > >> The Diskette Experiments, Phase III >> ---------------------------------- >> >> The Test Disks >> -------------- > >[...] > >> Drunk Disk >> ---------- > >[...] > > >> Conclusion: The disk is unreadable due to a >> physical (non-bit) failure of the disk jacket >> and internal disk mylar heavily sticking to the >> jacket itself. > >My first reaction would the to open up one side of the jacket, slide out >the disk (and keep it the right way up!), clean the surface of said disk >and then either 'mount a naked floppy' or use a spare jacket. > >It would be interesting to know if the data could be recovered if you did >that (in all 3 cases). I've had media both soaked and dried after soaking with various sticky beverages. I've found they cleaned up fine and read with out dificulty. I've mounted them with out the jacket and using an old one with cleaned and dried media. Generally floppies do not like any abrasive damage, holes, some solvents and of course magnetic fields. Other than that it's amazing what will survive. Allison

18 years, 2 months

Ambra 486 BIOS

by compoobah＠valleyimplants.com

AMBRA was made by IBM if my memory isn't faulty. It's very likely that much of the firmware is similar to IBM BIOSes. Unfortunately, I don't have any experience with IBM PC systems of the 1991 era.

18 years, 2 months

Addendum to Diskette Experiments, Phase III

by aliensrcooluk＠yahoo.co.uk

Hi, Paul posted this a day or so after the other post and it seems the Hot & Cold Affair disk did work again after leaving it overnight (see below). Regards, Andrew B aliensrcooluk at yahoo.co.uk --- Paul Panks <lumberjacks76 at lycos.com> wrote: There is an addendum added to yesterday's posting of Phase III of the Diskette Experiments. Here is the addendum: A new conclusion has been reached regarding the second disk experiment. Additionally, the final Phase III conclusion has been modified somewhat to showcase this change: "The Hot and Cold Affair ----------------------- This test called for putting ice cubes on the front side of the disk, while simultaneously holding the back side of the disk over a stovetop range at Medium heat (held approximately 3/4th of a foot from the surface of the stovetop due to overwhelming heat and potential hand burn considerations). The disk was held over the surface for a period of ten (10) minutes, while carefully juggling the ice cubes on the 1st surface simultaneously. The disk was allowed to cool for a period of 20 minutes, then read. The result was a disk that did not read, as the internal mylar floppy could barely be moved by force from side to side by this person. Conclusion: The disk was unreadable due to a physical (non-bit) failure of the disk jacket and internal disk mylar semi-sticking to the jacket itself. However, after waiting overnight and trying the disk again, it read without error. Performing a simple read/write on the disk -- writing (then reading back) a 2 block sequential file -- worked flawlessly. Although heating the disk and placing icecubes atop it is not recommended, the disk nonetheless did recover once it was allowed to cool overnight." The conclusion has also been modified somewhat. Here is the change: "Experiment Phase III Conclusions -------------------------------- Two of the disks were a total loss, as the experiment never progressed beyond the first question asked ("Could a disk still be read by the disk drive?"). The disk in the "Hot/Cold Affair" experiment failed at first, but then worked upon waiting 24 hours for the internal disk mylar to cool overnight. Disks are not impervious to permanent and irreversible physical damage from oatmeal, milk, water, heat ( >= 250 degrees F ), ice cubes, shoes and golf spikes. Heating a disk and placing ice cubes atop it will cause it to temporarily become unreadable, although the disk should return to working order within 24 hours. It is nonetheless strongly recommended by this person that end users strictly avoid such implements (as described above) when at, near or around a floppy disk or drive." The entirety of the Diskette Experiments can be viewed online here: http://www.geocities.com/dunric/diskfun.txt Paul

18 years, 2 months

FW: Third round of Diskette Experiments completed (results)

by ajp166＠bellatlantic.net

> >Subject: Re: FW: Third round of Diskette Experiments completed (results) > From: Jules Richardson <julesrichardsonuk at yahoo.co.uk> > Date: Fri, 29 Sep 2006 15:54:51 +0000 > To: General Discussion: On-Topic and Off-Topic Posts <cctalk at classiccmp.org> > >Allison wrote: >> Generally floppies do not like any abrasive damage, holes, some solvents >> and of course magnetic fields. Other than that it's amazing what >> will survive. > >.... unless it's a 3.5" floppy made in the last 6 or so years, then you just >need to *look* at them funny and they fail :) Actually I was talkkking about 8 and 5,25 media I was trying to recover data from. >Actually, typically I find the failure rate to be about 2/3 - I don't think I >can think of a single other product that reaches the consumer with such a high >rating. Jules, The last time I'd seens that failure rate I started checking the drives. It seeems the drives had so much dust (at work) they were scraping the media to failure. Cleaned the drives and the problem would go away for a few months. The media was a the cheapest 3.5 available. What would happen is once the heads built up a mixute of media and dust it would routinely destroy disks after one use after that. Outside of that and outright bad drives I found 3.5" to be very reliable and somewhat more immune to some of the things that kill soft jacket disks. In fact when AOL was sending their virus out on 3.5" floppies (pre bloat) I'd use them and still have a few that see regular use. I figure they are as cheap as they come! Allison

18 years, 2 months

Anyone speak fluent Greek?

by evan＠snarc.net

I'm looking for someone to translate this page into English: http://www.itia.ntua.gr/twiki/bin/view/Main/MuseumItem00042 Thanks! - Evan K.

18 years, 2 months

Data General Nova 2 users, where are you?

by hachti＠hachti.de

Hi folks, I recently got a Data General Nova 2 CPU. It is a very late built OEM machine (Boards say ?1973 Data General but IC timestamps tell a different story from the time around 1977/1978). The machine came with 80kw (!!!!!) of core memory which is two an a half time of 32kw wich is the Nova's address space. The memory is banked by very simple MMU which bank-switches the lower 16k. If I power the unit up I can simply use 32kw of core. That seems to work. Have not yet worked out how the mmu is switched. Will worry about that later... After replacing the front panel lights I can manually read and write memory locations. And I *think* that the CPU works. At least basically. The machine is full of made in Germany boards made by some strange unknown OEM company. There is a Diablo disk drive with a diablo controller. The only function I can see at the moment is a red led on the controller which says "ready" in sync with the ready light on the disk drive. Drive looks good. If I try to boot the system via the built-in dma loading routine it simply hangs in an endless loop and nothing happens. At the moment I would be glad to hook up some kind of "standard tty" to the machine. Does the Nova 2 have a standard tty port built directly into the one-PCB cpu? That would be wonderful! If anybody can help me with tips, tricks, software, hardware, experience or any other interesting stuff and information - please let me know! I don't know what to do with the machine at the moment. I think I also could need some "standard peripherals" for the machine. Thanks a lot! Best wishes from Bavaria (!), Philipp :-)

18 years, 2 months

External MFM/ESDI?

by ISC277＠CLCILLINOIS.EDU

Well, I have a bunch of open expansion space in my RK07 cabinet, and I was thinking of somehow mounting the ESDI disks inside it. What sort of products exist for mounting these disks externally, probably in a seperate cabinet from the controller?

18 years, 2 months

NEC Bungo advertisement on YouTube

by cclist＠sydex.com

Kind of cool: http://youtube.com/watch?v=0qG6uWO5HUc&search=mini-t Anyone have one of these? Cheers, Chuck

18 years, 2 months

SCSI taxonomy

by compoobah＠valleyimplants.com

I think that F/W SCSI-II (FAST-10) predated Ultra (FAST-20) by a few years, anyway: F/W SCSI was available on the SGI Onyx (in either diff or SE) which was introduced in 1993. I'm a big fan of SCA drives + adaptors for old systems since the 50-pin drives are noticeably ancient now (most at around 1998 or before). A SCA drive + 50-pin adaptor is much newer (and 50-pin drives of any capacity (9GB+) have a substantial premium over SCA and 68-pin models. Some machines (Sun lunchboxes in particular) don't have space for a SCA drive + adaptor board, though. The latest SCSI standard (SCSI-IV I think) no longer requires drives to support 8-bit transfers and asynchronous mode. Some of the drives I've seen still do, but be warned...

18 years, 2 months

NEC PC 98 site

by cclist＠sydex.com

I ran across a Japanese site that seems to specialize in selling NEC PC 9801-family items. I don't know how many 9801's ever made it to the USA, but the architecture's fairly common in the CNC machine tools world. http://www.pc98factory.com/ Cheers, Chuck

18 years, 2 months

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test-drb September 2006