Hello Jan,

JP>>>>> AND I have some MDISKs, supposed to last a century.
HD>>>> What's that MDISKs?
JP>>> Dutch:
JP>>>  https://nl.wikipedia.org/wiki/M-DISC
JP>>> English:
JP>>>  https://en.wikipedia.org/wiki/M-DISC
HD>> Nice to read and see.
HD>> But if that disks survives 100 years,
HD>> does the drives to read them still exists?

JP> Good question.

JP> I once used 51/4 inch floppies for my CP/M system.

Me too ;-).

JP> Then one day the disc drive failed.
JP> I still do have a USB drive for 3.5 inch floppies...

Me too.
Do you know if it is possible to get that USB Floppy disk drive working at a
Raspberry Pi?, to stay on topic ;-)
One strange thing about it:
First you got a floppy to install a CD drive.
With this USB floppy drive, we got a CD to install that floppy drive ;-).
Do you see the discrepancy of that?
This drive is OK at windows machines, but unfortunately I could not get it
reading and writing Acorn formatted DFS and ADFS floppy disks, even not with
the Virtual Acorn RiscPC emulator, sad.
The internal floppy drive luckily could.

JP> And a lot of those, even with old win 3.1 on it.

Nowadays I only use 3.5" floppies to exchange files between my old UniCorn BBS
DOS machine and the Acorn RiscPC standing besides it.
Up to 1 M. files that's faster than arranging a rs232c nul modem cable and
terminal programs te work together.
They cable is ready, but to start up the transferprograms and transfer takes
time. I only do that for larger files than a 3.5" floppy can accept.

HD>> You know electronics does not stay forever working,
HD>> especially not the capacitors in it, they dry out.
JP> You sort of hope that when a later civilization digs up our old optical
JP> disks the archaeologists will go to some university and have them 'decode'
JP> what is on it...

Yes ;-)
For that same reason I have an old Acorn BBC B computer with both the 8271 FDC
and the WD1770 FDC to convert almost every known diskfile format between 5.25"
and 3.5" disks, and even cassette tape files.
Tape was slow, but I liked the idea at that short period in 1984.
Within six months I bought a 2 x 80 Tr. DS/DD 5.25" Mitsubishi drives.
At first 200 kb at a side. They still work today, even with ADFS!
lateron I exhanged one 5.25" drive for a 3.5 DS/DD one to have better
exchanging capabilities.
At the Acorn Atom club we even build a "TROG".
It was a box of 10 DIN busses in it connected to only one computer with
diskdrive. Every member took his cassette tape (even a big reel one) with him
at the club, and all started recording, when the disk guy saves the file at
their tapes. It was a very nices idea to see.
I also built one for use at our Big Ben Club with the Acorn BBC B.
Not for intensively use, but only for showing the technique ;-).
TROG = Tape Recording Of Groups.
It does not work with the BBC Master, as their tape signal is to weak.
The Acorn BBC B had the most robust tape electronics ever made,
much better that every other make that days. That's why it was expensive.

HD>> I once hope to see an affordable storage system that has a long stay
HD>> independend of a large temperature shift, dust and humidity etc.
HD>> At the moment backing up to several harddisks every 10 years at different
HD>> places is also a reliable way, of course never 100%,
HD>> but at least it comes nearby that figure.

JP> I have a big alu box (BIG) with close to a thousand optical disks,
JP> from old CD-R, CD-RW, DVD-R, DVD-RW, and bluray.
JP> The interesting thing is, as it is 100% light proof, I get still zero
JP> errors on most old CD-R last time I looked.
JP> Some go back to year 2000 or 2001. 18 years.
JP> The trick: store optical disk in the dark.

YES.

JP> And dry,. I had to return some that had some fungus spots in it when
JP> new.

JP> And I have a 1TB disc with magnetic backups of much stuff.

I am still looking for a bulk erase box, such as the Akai ATE7.
You can fill it with a complete big 10.5" audio tape reel and when swithed on,
it erases the complete tape in only a few seconds.
It can also be ussed to erase floppy disks.
I think that's a save way to eliminate secure private data and to renew
magnetical media for fresh use (formatting) again.
Tandy corporation also sold a small one in 1986, but that was a simple one
costing a fortune for DFL=NLG 99,50 relatively very expensive that time.

Note: My Akai 635D tape deck for 1100 meter audiotapes at 10.5" reels is still
usable. I hardly use it anymore because of my bad hearing ;-(.
You donot know, but I got 4 times a hearing crisis with big losses,
The third one called a sudden deafness in 1993.
So I am now very carefull to keep my hearing as stable as possible.
And after 22 years I stopped wearing a so called "BiCros" hearing aid in 1997
after the 4th crisis.
That's why it is going relatively better with me now, still missing 67 dBA
right, and left no hearing at all since my birth.
But I am happy with what I am doing now with sailing and computing and some
voluntary jobs.

Henri.

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