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tezza
March 8th, 2008, 11:48 PM
Hi,

Just thought ppl might like to hear about my stringy floppy adventure today.

The stringy floppy drive replaced the cassette player as storage media of choice on my TRS-80 clone for about a year until disk drives fell to within my reach (see http://www.webweavers.co.nz/system-80/hardware_accessories.htm#stringy) . When I fired up the machine last year after years of inactivity I found the belt had perished.

billdeg (of this forum) kindly sent me a new belt for my beltless stringy floppy drive (thanks Bill). It arrived yesterday. This afternoon with the new belt in place, I fired up the stringy floppy drive to see which of my many wafers could be read.

Holy gunk Batman! After every second wafer I needed to clean the head and spindle with Isopropyl alcohol, such was the build up of residue. I guess that could be expected considering these wafers hadn’t seen the inside of the drive for 25 years.

Anyway, after an afternoon and evening of testing the statistics are:

Wafers that snapped – 21
Wafers eaten by the drive – 2
Wafers where the tape jammed up inside the cartridge and would not spool – 31
Wafers that seemed ok but would not format (media damaged) – 7
Wafers that formatted. (so were ok) – 14

Better than I could have hoped probably considering thy spent 15 years in a roof cavity under iron where temperatures easily reached 65 deg Celsius or more in the summer. Of course I never considered vintage computing would ever be a hobby way back then.

Anyway, it’s cool to have a stringy floppy drive now hanging off my 16k TRS-80 Model 1 AND to have at least SOME wafers that are still ok.

I’ve uploaded some pics of today’s project.

carlsson
March 9th, 2008, 12:52 AM
So, 14/75 still were working? That's inbetween 1/5 and 1/6.

tezza
March 9th, 2008, 01:02 AM
So, 14/75 still were working? That's inbetween 1/5 and 1/6.

Yes, not good but at least there were a few that seem ok. Thankfully I had lots of them. I'd forgotten I had so many. I must have spent a fortune on them back there.

The interesting thing is most of the wafers that are ok are the ones with longer ribbons. The 50 inch and even 75 inch lengths as opposed to the 20 inch or 10 inch. The latter tended to snap or jam.

When the wafers were new, it was the longer ones that were more troublesome. Whenever a wafer was eaten, it tended to be those ones. They seemed to have survived the years of abuse better though?

billdeg
March 9th, 2008, 07:30 PM
Great to hear. I am in the middle of cataloging all of my working ESF programs. I have been side-tracked by other projects, but soon enough I'll get through it all.
...a few screen shots taken during testing:
http://www.vintagecomputer.net/tandy/trs80_1/exatron_stringy_floppy/

I sold my spare drive on Ebay last week.

What's next...

1. Implement a method for converting wafer contents to cassette (Users guide has instructions)

2. Implement a method for converting wafer contents to disk
The issue with #2; you can't have the expansion unit and the ESF operating at the same time because they use the same expansion port. So what I believe you have to do is set up two TRS 80's and share one cassette drive. The first TRS 80 will have the stringy floppy and the cassette, the 2nd will share the same cassette (using a switch box) player and will also interface with EI and disk drive. The cassette will act as the bridge.

3. A method for recording the cassette copies as WAV files that can in turn be used on modern machines.

4. Disassembling code, printing assembly code directly from wafer, including data files.

tezza
March 10th, 2008, 02:31 AM
Bill,

Yes, it will be good to get that software into a more standard format for archiving purposes.

I was pleased that FMS (File Management System) program was one of only two of my many wafers that actually still had intact programs. Alas, Electric Spreadsheet and Scripsit for ESF were not so lucky. It would be great to have these archived somewhere on the net in case they are lost forever.

billdeg
March 10th, 2008, 03:53 AM
Here is a list of the working programs I have on wafer, so far.

Exatron Stringy OS (ESOS)
Forth 10
FMS Formatter (does what?)
R/S Ed/Assemb patchs
Patchword for Scriptsit (loads but does not do anything I can identify)
Scriplus
Epson Sample TR
Tcopy /20435
Zbug /17208
a demo wafer for ??
what's on it? and data file
Simple Simon (disassemb)
Color code trainer
Perpetual calendar
@freeze
Castle Shot (with programming error)
Electronic Spreadsheet
Analogies

I have not found a working copy of Scripsit yet, not sure if Scriplus is "Scripsit Plus" or can read regular scripsit programs.

Much work to do.

tezza
March 11th, 2008, 01:01 AM
Here is a list of the working programs I have on wafer, so far.

...
FMS Formatter (does what?)
....


Hmm.. I think this is on my FMS wafer too. Not sure now what it does. I may have the FMS instructions in my huge pile of TRS-80 literature somewhere?



...
@freeze
...


@Freeze. @Freeze??? That rings a bell deep in the old memory RAM somewhere. I used to know what that did years ago, but not now :)

billdeg
March 18th, 2008, 04:42 AM
Tezza/All,

Hi - I am attempting to recover data from a wafer that *may* have a Scripsit data file on it. The command to load a document from tape/disk Scripsit is

BREAK L [docname] {enter} - load from disk or tape depending on what kind of scripsit you have (tape or disk).

BREAK L,T {enter} - load from tape if using disk version and you want to load a tape.

I am working from the assumption that ESF Scripsit is the tape version.

I can get to the prompt to ask for the data file, and I simply swap the wafer before hand, but what about cases where I have a 2nd stringy drive assigned as drive 1? It's so much easier to work with two ESF's if you have them.


thanks.

Bill

tezza
March 19th, 2008, 12:20 AM
Hi Bill,

Are you talking about a scripsit data file from from the ESF version of Scripsit? I have documentation for a program called "Patchword" which patched cassette scripsit to work off an ESF and to save and load Scripsit files to wafer.

Some commands in this ESF patched version of Scripsit include the following :

(the F=n is the file designator where n=1 to 99, D=d is the drive designator where d=esf drive number. The equal signs are optional. Square brackets below are also optional)

<BREAK> N [F=n] [D=d] <ENTER> initialises a wafer (i.e. is the same as the @NEW command)

<BREAK> S F=n [D=d] <ENTER> saves a document on wafer as file n.

<BREAK> L [F=n] [D=d] <ENTER> loads a document. (verfication is automatic).

Hope this helps. I dug through my big box of docs tonight and found my old scripsit manual and there pasted in the front was the instructions for "Patchword: A stringy floppy Patch for Radio Shack's SCRIPTSIT by Philip C. Pilgrim, Discovery Bay Software, 1980." This is the patch program I used to convert Cassette Scripsit to ESF Scripsit.

If this is the same patched version you have those commands should work. Let me know if you want the Patchword Manual. It's only a few pages and I could PDF it and email it if you want.

billdeg
March 19th, 2008, 07:44 AM
Through the magic of a little manic testing I was able to figure it out yesterday night. Thanks for confirming. I have a wafer with both a regular and a patched version of Scripsit. I also have the patch program. It requires ROM 4.1, on of my stringy floppy drives is 3.4 ROM.

Alas, the wafer I was checking did not have any scripsit files.

Do you know of any programs that perform a directory of a stringy wafer? I have something called "what's on it" but I still have to see...what's on it.

Bill

Bungo Pony
March 31st, 2008, 07:18 AM
Holy gunk Batman! After every second wafer I needed to clean the head and spindle with Isopropyl alcohol, such was the build up of residue. I guess that could be expected considering these wafers hadn’t seen the inside of the drive for 25 years.

You can temporarily restore these tapes by baking them at 125 F (50 C) for about six hours or so. Let them cool for 24 hours, and they will be temporarily useful again - at least long enough to pull the data off them.

I had to restore my reel 2 reel tapes like this to get the audio off them. Shedding tape / lubricant and sticky residue is extremely messy.

barythrin
March 31st, 2008, 02:26 PM
That's interesting. So is that baking trick just for those wafers in specific? I've never seen stringy floppies so I'm not really sure what they are, they look like tapes from your pictures but I guess they are not a magnetic film inside?

kb2syd
March 31st, 2008, 02:30 PM
They're tapes. The carrier that holds the magnetic media to the substrate can get gooey. Baking fixes (as in hardens) the carrier a bit. Usually at least enough for a couple of reads.

We've done this with 4 and 8 track audio masters.

Temperature is critical too. Too hot and it may warp the cartridge.

barythrin
March 31st, 2008, 02:45 PM
Can this trick be used on regular audio tape? (I guess that's 4 track?) Do you use a similar temperature? I'm just curious.. I wouldn't try this on a cassette that's working but it would be interesting to try assuming I don't come out of it with a nicely blackened baked tape. What surface would you place the tape on since I would think a metal pizza pan or something would increase the temperature?

On an off-topic but similar story when I worked at AMD some of the first K7s (preproduction) had some flaw in them that if they got over a certain temperature some of the metal inside the chips could melt and result in some connections no longer being made properly or a dead processor. Similarly one engineer commented if the users just bake the chip for a few hours in the oven it'll fix it.

Druid6900
March 31st, 2008, 07:35 PM
Yeah, nothing worse than a half-baked processor, I always say :)

tezza
April 1st, 2008, 12:39 AM
You can temporarily restore these tapes by baking them at 125 F (50 C) for about six hours or so. Let them cool for 24 hours, and they will be temporarily useful again - at least long enough to pull the data off them.

I had to restore my reel 2 reel tapes like this to get the audio off them. Shedding tape / lubricant and sticky residue is extremely messy.

Interesting!

I wish I'd known this. I threw enough damaged ones away to fill several oven trays! :)

Bungo Pony
April 1st, 2008, 03:46 AM
Actually, a regular kitchen oven is too hot. Believe it or not, a temperature regulated Food Dehydrator would work much better.

I use a temperature chamber I built myself out of an old microwave oven, a hair dryer, and a temperature control. It works quite well :)

kb2syd
April 1st, 2008, 05:07 AM
There is also waaaay too much humidity in the average propane oven. We use an oven as the enclosure and a hot plate to add the heat.

Bungo Pony
April 1st, 2008, 03:47 PM
Can this trick be used on regular audio tape?

Yes. If you have an old cassette that's squealing on the heads, baking it will fix it.


I wouldn't try this on a cassette that's working but it would be interesting to try assuming I don't come out of it with a nicely blackened baked tape.

That's why you need something that's temperature regulated. 50 degrees celcius isn't hot enough to burn plastic. Also baking a working audio tape is kinda pointless since you won't be able to tell if your experiment worked.


What surface would you place the tape on since I would think a metal pizza pan or something would increase the temperature?

Actually, it's better if you put take the tape out of the plastic shell to bake it. I had to wind my reel to reel tapes onto a metal reel. The temperature chambre I used at work to bake my reels has a metal bottom in it as well as my home made rig.

One thing that would be a good idea is to make sure your tape has an even "pack". If you look at the spool of tape and see ridges, the pack is uneven. I had a terrible time re-packing my shedding tapes for baking. I had to re-route them through the player to only use the capstan & pinch roller. By the end of some tapes, my capstan would be either brown or white from all the shedding.

Also, beware when baking tapes made in the 1960s. Some of them were made with acetate and baking them will make them worse.

I made a page on my website about tape baking if you wanna look at it:

http://www.mts.net/~bpony/cparchive.htm

marmotking
January 9th, 2013, 04:03 PM
Hey, what happened to the tape baking page? You got my curiosity up!

Chuck(G)
January 9th, 2013, 04:51 PM
Anyone remember the whole "Ode to the Stringy Floppy" doggerel that came out sometine in the 70/80s in one of Exatron's newsletters? I think it started with "I love my stringy floppy..."

Dustym
January 11th, 2013, 12:34 AM
Well done Tezza, you've had a much better return on good wafers than I've had with my Aculab Floppy Tape. So far 100% failure! I'm wondering if I've a hardware problem it's that bad!!
I'm still waiting/hoping Matthew Reed will alter his M1 emulator of allow an FT as well as a SF to run. It's something to do with memory allocation I think. The FT takes up more 'room' than the SF! The ROM is larger and more advanced! I've a copy of the ROM ready and waiting to go!

tezza
January 11th, 2013, 07:46 AM
It's good that you have the ROM Dusty. Yes, I was very please Matthew elected to include the ESF in his emulator. The peripheral played a large part in my early microcomputer experience.

I only wish I had more imaged ESF software. I had a great statistics package called tinytab (like Minitab) which came on about 8 wafers. It was all in BASIC and used chaining to hold the variables as you swapped between functions by swapping tapes. What's more it was written locally. Unfortunately I couldn't save it. When I tried to image it the master wafer didn't want to load in the program, then it snapped!

Such are the breaks.

Tez

billdeg
January 11th, 2013, 08:52 AM
I am getting closer schedule-wise to taking on the project of imaging all wafers I have.

tezza
January 11th, 2013, 08:59 AM
I am getting closer schedule-wise to taking on the project of imaging all wafers I have.

That would be great Bill!