Trials, tribulations, and observances 300 disks into..

[Keatah]

Trials, tribulations, and observances 300 disks into imaging my stash of just under 4000 floppies.

 

1- Don't run the drives non-stop. After imaging 80 or so disks back-to-back, flipping and flicking them in and out of the drive while ADTpro sends the final tracks (and using simple number filenames) the heads got warm enough to lift the oxide and coating off of some cheap disks. It rolled up like micro-sized bits of dough, squealed and smoked a bit (no pun intended), and deformed the floppy substrate. Caused plenty of downtime while I disassembled the drive and manually cleaned the heads. See point #9 for more.

 

2- Adjust drive speed at 299.5 RPM.

 

3- Have a labeling system in place. As disks are imaged, make a tag an attach it to the envelope with a fold. Associate the number with a text-file list.

 

4- Use the Windows File System and Explorer to search a local copy of ftp asimov to see if something has been posted. This doesn't eliminate imaging the disk in question, but it's good to know.

 

5- Make note of copy-protected images for preservation with kryoflux.

 

6- Have a copy of Applewin, Ciderpress, SaltinesSuperTranscopy(sst), Copy II+ 5.5, 8.4, at the ready so that you may look into images and verify and examine versions. These tools are invaluable because they work quickly when run in emulation with no speed limits. They allow you to look at files, read text, prepare compilations, and even take a break and play a game.

 

7- Be prepared to clean the heads after imaging each really really old disk. Some brands hold up perfectly, others are getting weak. A head cleaning disk is ABSOLUTELY VITAL here. And you can certainly get more than the 10-15 recommended uses from one. More like 50 to 100 or more! You only need run then for 10 seconds or thereabouts. Use alcohol. Even water+alcohol for problem dirt.

 

8- Have a stash of blank disks ready for recovery of weak disks.

 

9- Have a bit copier ready to handle delicate disks. Why? So that the disk rotates as little as possible, and a cooling period is present. So the disk surface never rises above ambient and there is no temperature gradient to delaminate the oxide and lube surface.

 

It isn't so much important to use a "bit-copier" as it is to take it slowly. A modified COPYA or anything else "slow" would likely work.

 

A full-on ADTpro transfer overheats the head and surface of these delicate disks. The oxide sheds, it binds up, makes more friction and soon enough burns a track you can almost feel and definitely see.

 

So a bit copier is used. Copy the odd tracks, then the even tracks, like skipping by two. As the bit copier spends time "analyzing" the track, it has time too cool down. The delay is long enough to allow you to even partly eject the disk, swab the head clean, and close the door.

 

These disks live for only one read at best. A 30 second ADTpro transfer session is absolutely deadly and read errors happen in as few as 4 tracks.

 

10- Over the years I took a Disk II drive and incorporated a number of enhancements and mods as part of an ongoing project testbed. Something to work on when I got bored and to learn new skills. Cumulatively this souped up drive has:

1- Variable gain pre-amp on the R/W head w/display
2- PWM rotational speed control w/display
3- 7-segment LED display of current track and sector
4- 3-position toggle switch for write-protect, no write-protect, or default
5- Toggle switch for Disk 1 or Disk 2 position
6- Output of shift register to logic analyzer and buffer (incomplete)
7- In-use indicator Red=write, Green=read
8- Electrically adjustable track alignment over 2-track range with 1/16th track resolution

9- 3-axis adjustable pressure pad

10- Stabilized power supply

11- High quality connectors and no sockets

 

It was strictly a testbed for things, but now it has become invaluable and I'm using it to help work with the disks literally falling apart. Feature 9 is going to be important because this can be used to change how much the disk flexes as it rides over the head.

 

11- One boatload of patience and cargo ship of time. It can take an entire day to capture disks that completely unreadable in standard drives.

 

 

[Keatah]

12- An archiving program on the PC so that you may collect the thousands of files into one. AND a separate folder to provide instant access and allow MDC to read the disks if you want to search for a specific file within thousands of images. Don't forget versioning backups on occasion.

 

13- Practical working knowledge of your file archiver and the Windows' file system. And all your other tools and utilities. This isn't the time to be learning. You're going to have enough other problems and recalcitrant disks to deal with. And you need to know when the problem is a tool issue or a disk issue.

 

14- An assortment of DDD versions handy if you're working with files downloaded from the old BBS'es.

 

15- Blank images on the emulator side of things. Both DOS order and nibble.

 

16- Checksum program for comparing images from marginal disks.

Edited October 1, 2016 by Keatah

[trash_44fr]

10- Over the years I took a Disk II drive and incorporated a number of enhancements and mods as part of an ongoing project testbed. Something to work on when I got bored and to learn new skills. Cumulatively this souped up drive has:

1- Variable gain pre-amp on the R/W head w/display

2- PWM rotational speed control w/display

3- 7-segment LED display of current track and sector

4- 3-position toggle switch for write-protect, no write-protect, or default

5- Toggle switch for Disk 1 or Disk 2 position

6- Output of shift register to logic analyzer and buffer (incomplete)

7- In-use indicator Red=write, Green=read

8- Electrically adjustable track alignment over 2-track range with 1/16th track resolution

9- 3-axis adjustable pressure pad

10- Stabilized power supply

11- High quality connectors and no sockets

 

 

Can you post pictures of this drive ?

It would be awesome if you could document all the mods (#4 & #7 are already available in the FAQ though).

[Keatah]

I'm working on a doc that describes what features are useful where and some pictures will go along with it. Especially in light of how I'm currently using it.

 

Meantime back to battling Murphy's Law. Some cool stuff doesn't read too well. And crap stuff or stuff already cracked 5x reads just fine. And I don't even like those games anyways..

[JamesD]

The crap reads fine because the disks weren't used much

[Keatah]

That's true for 50% of the disks. The other 50% weren't used at all, beyond initially writing them. I'm surprisingly having an equal amount of difficulty whether they were used or not.

 

I think that homemade disks, on drives with dirty heads, are the worst and weakest today. I recall back in the day I wore a few disks out, and clearly marked them. I Just lost RAXTERM to the ravages of time. Same with COUNTY CARNIVAL. A couple of sectors were simply too weak to get anything back. And this disk was hardly used at all. I set it aside for spin-stand analysis later.

 

But what bothers me are things like the original BUG ATTACK. I think this is a multi-load game, but all the cracks are single-file loads at 130-sectors.

 

Actually it bothers me a lot.. that a name or program, whatever, shows up in the archive of the day and boom, it's considered done and done with. Versions aren't checked. Functionality isn't checked. Completeness isn't checked.

 

It's like Jeeves, J needs an interrupt generator card or dongle of a sort, a simple 3 TTL chip mini-card.. And yet no mention is made of it. Just that duhhh it doesn't work?!?! Why?

 

IDK, I think the whole game of preservation can be upped considerably.

 

And then we have online archives falling into disrepair.. which is a topic I care not to discuss right now.

[Flojomojo]

Hey hey! You're actually doing this! Well done, you!!

 

Sounds like uploading to someplace like archive.org in addition to Asimov might be in order.

[Keatah]

Asimov is out, hasn't been updated in a long time. I think my material deserves better than to be left sitting around. Archive.org is a possibility. Looks like a lot is involved in making a single upload. I'll have to see how it goes.

[Keatah]

It is time to stop imaging when you realize the head cleaner disk doesn't translate into .dsk format.

[Keatah]

Went to go buy a head cleaner disk from fleabay, I lit mine on fire accidentally.

 

They want frakking $25. Nope.

 

The ones for $7-$12 won't work and will abrade the pressure pad. You need one that has the plastic shield on it. And those seem to go for $25, or even $70. Uhm no..

[Keatah]

..working on a couple of fungus-infected disks. They read ok, and surface looks smooth under a microscope, but the drive changes pitch and whines when the spots pass under the head. Some of the spots are removable with water, some with alcohol, and yet some with 3M platter cleaner fluorocarbon. There doesn't seem to be universal do-it-all solution. Leads me to believe there are multiple strains.

 

I intend to culture it and see exactly what it is. Maybe I can get time on an electron microscope or something.

Edited October 5, 2016 by Keatah

[Keatah]

Still finding more shit like Ghostbusters, Paperboy, Gauntlet, MarbleMadness, Ultima.. These things read like a psychic on caffiene.

 

But the good news is I recovered Raxterm, don't know what it does but all the files check out. I buffed away the infected coating and resealed the area. Good as new and reads like the other sectors. How long will the repair last? Who knows.. Who cares..

 

It was interesting to see the head hit the fungus bump and jump over part of the next sector. And it was that next sector I suspect wasn't reading. Either way. It works now.

[Great Hierophant]

I have a Radio Shack 5.25" drive cleaning disk that came with flurocarbon cleaning fluid. I have read that flurocarbon-based cleaning fluids are superior to alcohol for cleaning disk heads, but that it is no longer available because it depletes ozone.

[Keatah]

In small applications, such as my project here, I wonder if the new eco shit doesn't cause more insult to the environment because I have to use more of it, and additional supporting "stuff" to get the job done.

 

Ohh well, not my job to worry about it. The amount of damage I can do in a whole year is utterly and totally dwarfed by any one random mistake on a procedure sheet at a fortune 500 company. Bring on the fluorocarbons!