I'd be interested as well, same situation. On Fri, Oct 29, 2010 at 4:24 PM, Jason T <silent700 at gmail.com> wrote:

On 10/29/2010 4:24 PM, Jason T wrote: Once I have cleaned the drives properly and verified that the disks actually *work* and so forth, I'd be happy to make copy of the disks for anyone that wants them for the cost of shipping. I don't believe I have a lot of free 8" media so I think you'll have to provide that unless you're in a pinch, then let me know and I'll try to dig you up at least a TRS-DOS disk. Nathan -- -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- Nathan Pralle, Computer Geek Email: nathan at nathanpralle.com Web: http://www.nathanpralle.com Blog: http://www.philosyphia.com Twitter: http://twitter.com/NathanPralle -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-

Talking'bout that, I got a Quantum DLT4000 drive...I could use some DLT tapes for this drive :oD

On 30 Oct 2010 at 19:47, Tony Duell wrote: Well, he could have a 220V 50Hz model and be running it on 120V 60Hz (the motor will develop sufficient torque to spin the disk). I've made that mistake once. The results from the reverse would be "interesting"... --Chuck

Y'all are making me miss my tandy model 16 and 6000.

On 10/30/2010 1:47 PM, Tony Duell wrote: They probably are, that's a good point. I don't know yet; I have yet to yank them to find out. I'm going to try to dig out the machine this week. I want to make sure I clean the heads and so forth correctly and do all the alignment, etc. to make sure everything's in shape before I shove these disks in there, just in case something's off/corroded/etc. and I end up with a pile of ferrous shavings instead of data. ;) Nathan -- -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- Nathan Pralle, Computer Geek Email: nathan at nathanpralle.com Web: http://www.nathanpralle.com Blog: http://www.philosyphia.com Twitter: http://twitter.com/NathanPralle -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-

Funny history: I was 13, 14 year old. I don't remember well. I'm getting old. A friend of mine was directing me in the field of computer repair. I had just bought my first apple II clone (An Exato Pro II from CCE) with a controller board and a full height 5 1/4 floppy. Mine had a problem in the CA3361 (if I'm not mistaken, we are talking 22 years ago) transistor array, so it could read disks, but not write. Marcelo (my friend) was showing me how to align the drive using locksmith 6.0, reading a disk and finding the middle point in the rotacional position of the step motor. Ok, I aligned the drive, but it shown some read errors. The head was dirty. So, he wetted his finger on the mouth, rubbed the wet finger in the drive head, cleaned with his shirt..."Presto, it works!" he said. And unbelieveably, it was clean and working as it should always had. I shouted loud...For me, he had finished my drive. But I learned that things in the floppie world wasn't so fragile as I have learned before. And i cleaned my drives many times using this method, when there wasn't alchool around. I should write a book ;o)

On 11/2/10, Terry Stewart <terry at webweavers.co.nz> wrote: That's the tried-and-true way of reading a diskette that's had Coke spilled on it. After the world switched to 3.5" floppies, doing these sorts of things (mostly) faded into the mists. -ethan

Don't you hate it when those things shrink like that? ;-)

I am seriosulyt worried by the fact that a group of programmers who are capable of writing a compiler didn't realise the value of backups. I can't beklieve tht nobody had ever lost data before. -tony

Terry Stewart [terry at webweavers.co.nz] wrote: I guess you know already but I keep coming across people who think that RAID means you'll never need to backup again. Quite how they expect to recover from accidentally deleting something important beats me. In passing, I don't think that drives are *that* reliable these days. Once you're past infant mortality then I'd expect to get a good 5 years out of a drive, but that passes sooner than you'd think (or maybe people upgrade well before that happens :-)). Perhaps SSDs will change the playing field a little, but overall I doubt that reliability levels will shoot up drastically: there's always something that can be shaved slightly thinner to save a few pennies (and if things don't go wrong eventually, how can you sell them a shinier widget?). Antonio

Yes, thats' right. I zapped a drive (actually a couple) once by getting the pin alignment wrong. http://www.classic-computers.org.nz/blog/2009-03-23-teac-apple-disk-drive-r… By the time I realised what what going on, I'd gone through a lot of my write-protected disks! Thank goodness for ADTPro! Terry Stewart (Tezza)

The classic case of that is a demountable hard disk with headcrash problem. It will damage any disk inserted into it, and those damaged disks will then casue headcrashes on any other drive they're tried im. Some indiots end up damaging every head and disk in the building.. Can it? According to the schematic in the Apple DOS manual (I've just dug it out), the wrtite protect switch will disable the Wr Req/ line by tri-statingB4c (a '125). The output is correcly pulled up to the inactive state by R16 under such conditions. Of course a problem on the analogue board can result in the thing corrupting disks, but that would apply to any drive. -tony

On Thu, Nov 04, 2010 at 10:19:24AM +1300, Terry Stewart wrote: You do, at least some of us ;-) At home, my server has all disks in RAID setups, either RAID1 or RAID5 to reduce the impact of individual disk failure. Of course RAID isn't a replacement for backup, so the data I don't want to lose gets written to DLT and LTO tapes (as well as DVD-RAM for some smaller stuff) from time to time. Backup media leaving the home are of course encrypted in case they get mislaid or "wander off". Some less critical data that doesn't warrant tape storage but would be annoying to lose is replicated over more than one machine. Disk is cheap these days. Kind regards, Alex. -- "Opportunity is missed by most people because it is dressed in overalls and looks like work." -- Thomas A. Edison

There really isn't any other option. I have several TB of data, and I use a set of 2TB drives as backups to the production 2TB drives. cost about $100 per drive. once a year, I replace the backup drives with new ones, whether they need it or not. this keeps the data/magnetic cohesion fresh and limits the possibility of loss. I can't use DVDs, because even a single 2TB drive would need about 450 disks. Plus if even one disk gets cracked, scratched or corrupted, there goes that data. Plus the cost is still higher than HDs would be (at least where I am). Blu-ray disks hold more, 25gb, still needs 200 of those, and the price is insane. Also DVDs and Blu-Ray disks would take hours (if not days, weeks, etc) to actually write with one burner. backing up one 2TB to another doesn't take long at all, still long, but much better. I'd love to see someone make a HD jukebox device Dan.

Since my primary use of my computer these days is to write software that runs under the PDP-11 instruction set (I use Ersatz-11 and sometimes SIMH), I find that backups throughout the day are essential as I make changes to the program. When I used a DEC CPU, I had only limited storage until the PDP-11/83 which finally had 3 * 600 MB Hitachi ESDI drives. At the end of a successful project, all 3 drives were identical. There were also (initially) TK70 backups of the data (required 3 tapes) or later Sony SMO S-501 media (required 3 sides of media). While writing a full TK70 tape took about 60 minutes, about double the time as the magneto optical, the big advantage of the latter was the random access nature of the media allowing any file to be accessed equally. In addition, the backup of a single RT-11 partition (32 MB) could also be done in just 4 minutes as opposed to having to write all 8 or all 4 partitions to the TK70 tape. When I shifted to the present Pentium III, I started with 3 * 40 GB ATA drives with the C: drive holding the current files and the D: and E: drives holding backups. I use GHOST to copy the C: drive to an image file which usually requires about 1 GB to hold all of the files from the C: drive. Once every 4 months, I copy 4 monthly backups to DVD for permanent storage, i.e. 3 DVDs a year to hold 12 monthly backups. I have been using the Pentium III since 2002 and replaced the 3 * 40 GB ATA drives with 3 * 134 GB ATA drives around 2007 after they started becoming unreliable. Since I find that software corruption is MUCH more likely a problem than hardware failure of all 3 drives, RAID does not seem to be very useful. Agreed!! As I develop a program, I make catastrophic errors which crash the operating system. For this reason, I found, by experience that running with the disk images in READ ONLY mode means that I never have to be concerned that any of the disk files are corrupted during testing. Just last year, I found that one of the standard development programs has a bug (been there for 20 years now) that causes the operating system (RT-11 obviously) to crash during one of the many operations leading from the source file to the final executable program file. Under Ersatz-11, that only means a "BOOT DU0:" again to get started and since the disk files are all in READ ONLY images, nothing ever gets lost. And whereas on the PDP-11/83, backing up a 32 MB RT-11 partition took about 4 minutes and an equal 4 minutes to verify, on the Pentium III under Ersatz-11, making a copy of a 32 MB image file to a backup image files takes only about 2 seconds. It is now easier to just backup the entire 32 MB image file as frequently as each file on the 32 MB disk image file is changed as I would have done with just the one file on the PDP-11/83 to the one file on the backup drive. So every time I spend 5 or 10 minutes editing a source file, I then spend the 2 seconds to make a backup copy even before I verify that the assembly is without any errors. Once or twice a month, I usually make such a blunder that it is easier to go back one step the day are a big help. And since they takes only 2 seconds and two keystrokes to invoke the command to one of 4 backup images, the overhead is too short to even consider a disadvantage. Over the past 30 years with DEC hardware, except for the RD53 drives, there were few outright failures before I could recover the contents and probably only about 5 drives (again except for the RD53s) actually failed. On the PC, it has been my experience that about 5 years is probably the limit. While failure is still usually graceful enough to recover all of the data if prompt action is taken, the warning is usually less than 1 week before the problems become worth much more than the cost of a replacement drive. If I don't finish my upgrade to a new core 2 duo system with 3 * 1TB SATA II drives by another year, I will probably have to replace the 3 ATA drives again. Over the past 8 years, I did experience 2 complete drive failures for unexplained reasons. Fortunately, everything had been backed up quite recently and GHOST was able completely recover the C: drive in one case and make another copy of the D: drive from the E: drive in the other case. The two complete losses of the physical drives (contents only) must have been software since GHOST recovered the whole drive without a problem and a LLF (Low Level Format) was not required. On the PC side of the files, I used to backup once a day. Now I find that my activity is low enough that 3 backups a month are sufficient with the end of month backup being retained for copy to the DVD. One VERY helpful aspect of GHOST is that along with the compressed image file of all the files on the C: drive, a text file with a list of all 10,051 files on the C: drive plus the last date modified and a 32-bit CRC is also produced. I quick run of FC.EXE lets me determine about how many and which files have changed from any previous backup. I decided to keep the FAT32 file structure for the new system with Windows XP since the version of GHOST does not support the CRC text file under NTFS. My present Pentium III system still runs very nicely under Windows 98SE. YES!!! Jerome Fine Yes! I can't understand how even major software projects are abandoned without reliable backups of the software. Most major software manufacturers (including DEC) did not bother to keep archived copies of each version of a release for more than a few years so that at this point, the hobby community is left with almost no historical record except that which the hobby users have found by themselves. Jerome Fine

I suspect far too many have :-( [..] My friends do, but they're the sort of people who, even if they now use a modern machine, have grown up with what are now classic computers and have learnt the value of backups. My view is that if something takes longer to recreate than to back up, then it should be backed up. So I probably wouldn't specifically back up an address label I'd typed in :-). Or the object files for a piece of software I was writing (rebuilding from the (backed up, of couse) source code is not a major job. But those source files, the source of amjor documentaiton I write, etc is backed up. Several times. Indeed. I suspect you are,. which is why I expressed suprise that a software development group didn;'t keep backups of its work... -tony

On 3 Nov 2010 at 20:30, Tony Duell wrote: It wasn't as bad as it sounds. Since implementation was "divide and conquer", copies of the source existed in some form among the members of the implemenation time. Executables were already widely distributed around the company and to a few customers. Had we lost the source entirely, the practical upshot would have been that someone would have had to spend a day recreating the source disks from team members' copies. We all had years in mainframe product development and were well aware of the fragility of electronic storage. That there was only one set containing the collected source would have mattered little. We'd come from an environment where you started a session with *no* files. At session end, any files created during the session were disposed of--certain names, such as OUTPUT and PUNCH were sent to their appropriate queues, while any other files were discarded. If you wanted to use a previously-created file or create a new "permanent" file, you had to specify its catalog name,version (you could have multiple versions of the same file), account and password, session permissions and the local file name (i.e., the local association) for that file. Backups were handled by system operations on a daily basis, so individual users never had to worry about making personal backups. Inadvertently deleting or modifying a "permanent" file was almost completely unknown. In comparison, Unix seems positively crude in the respect of data security (one aspect of which is to protect a user from himself). And micro-oriented operating systems such as ISIS or DOS are downright primitive. --Chuck

I didn't say that. And after Chuck's expanation (the data did exist elsewhere, and recreating the complete sources wouldn't be _that_ much work) I am less worried.... Oh, go ahead... But I beleive that cucifixion has never been used as a suicide method. -tony

Mike did not say that ...Neil did. -- Will

I have this image of 4 of those butane-powered nailers used by builders suitably arranged nad with a remote triggger facility. You get your arms and legs in the right places, somehow press the switch and bang... No I am NOT thinking of trying this.

Except that I am in the wrong country for this. Do you _really_ want me to try it? -tony

On Wed, 3 Nov 2010, Tony Duell wrote: It is one of the consequences when companies recruit straight out of colleges. Although not necessarily the cause in THIS case, it tends toward a work group who are strong on theory and very weak on real-world experience, who will fail to realize all of the things that could go wrong (such as using scanf() for USER input!, or not making backups ("Oh. The technicians always took care of THAT")) Look at the GREAT ideas, and stupid mistakes, on the Lisa dream team. -- Grumpy Ol' Fred cisin at xenosoft.com

On Thu, 4 Nov 2010, Teo Zenios wrote: Most of these are arguable, based on LOTS of theoretical knowledge, but a shortage of experience. Such as, The "Twiggy" THUMBPRINT diskette Choosing the BEST microprocessor, based on specs, without knowing that there was no prior software available. (I'm glad that they did, but it was ONE of the causes of the Lisa's market failure) Writing an operating system in Pascal High-res B&W graphics (was Jobs color-blind? That, and a closed system seem to have been his forte) Not having adequate software ready for the machine release Price point! ("The Maserati of the mind" for sale to a BMW market) To their credit, they didn't take too long to redesign it into a machine that could be sold at a more reasonable price (Mac) -- Grumpy Ol' Fred cisin at xenosoft.com

Don't you remember "verbatim datalife plus" which came with a spare sleeve you could cut the sleeve of your disk, take the internal disk out, insert in the sleeve and read (and use!) in the drive? :oD

On Thu, 4 Nov 2010, Andrew Burton wrote: Floppies used for testing always hold up just fine. It is only when you have excess reliance on one that it will fail.