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General Category => NC100, NC200, PCW, PDA600 - the rest of the Family! => Topic started by: GeoffB17 on 23:36, 19 January 23

Title: Use CF2 as CF2DD
Post by: GeoffB17 on 23:36, 19 January 23
Well, I've finally got myself a CF2DD drive to play with.

BUT, I always understood that you could try to format CF2 disks as CF2DD, and while it was not certain that they would, some would OK.

Now, I've just tried.   The first one I tried (Maxell) worked OK, and Verified OK.  I tried two more, and both failed, one almost immed, the other 3/4 of way through.   These were another Maxell, and a Panasonic.   So that's 1/3 of the disks I've tried.

What experiences have others had?   Is the chance better with 'virgin' disks, or should it not make any difference if the disk has been used before?   If the disk HAS been used before, does it help to use a magnet to wipe the disk?

Interested to know the experience of others.

Geoff
Title: Re: Use CF2 as CF2DD
Post by: SkulleateR on 23:49, 19 January 23
Early disks were labled as CF2DD or CF2-D but they are the same as CF2 disks ;)

http://fileformats.archiveteam.org/wiki/CF-2_Compact_Floppy_Disk
Title: Re: Use CF2 as CF2DD
Post by: GeoffB17 on 00:35, 20 January 23
Thanks for the note/link, but my understanding is that there was always just the one production line, but when some CF2DD disks were required, then a batch of CF2 disks were taken from the main line, and formatted as CF2DD.   Those that passed were then labelled as CF2DD and sold as such (at a higher price).  Those that failed were returned to the original line.  So many disks that COULD have passed the test were never tested, and remained in the general pool.

When I tried my test earlier, the two disks that failed were subsequently reformatted as CF2 and passed fine.

If I find that 1 out of 3 is 'par for the course', then that's OK, I'll know what to expect.

Long ago, there was a similar situation with DD 5.25" disks.   The normal format was 40t.   Then the 1.2Mb (80t) drives became common, but people still had piles of 40t disks.   I found a utility that would use the 1.2Mb drive to format the DD disks with 80t, to give a format the same as the DD 3.5" disks, i.e. just over 700k capacity.  The notes with the software suggested that not all disks would work.   But actually almost every disk that I tried, both branded and unbranded ones, worked perfectly and I prob had over 99% success.  I still have an old PC that defaults to that format even now, although this can be turned On/Off very easily.

My guess is that the situation with the CF2 disks will NOT be as helpful as that?

Geoff
Title: Re: Use CF2 as CF2DD
Post by: GUNHED on 17:00, 21 January 23
Never use a magnet please! There's a bunch of reasons, but I'm not going into detail, because I have no time for discussions.
Title: Re: Use CF2 as CF2DD
Post by: Audronic on 22:18, 21 January 23
Quote from: GUNHED on 17:00, 21 January 23Never use a magnet please! There's a bunch of reasons, but I'm not going into detail, because I have no time for discussions.
Hi Gunhed

---  WHY ---

Keep Safe

Ray
Title: Re: Use CF2 as CF2DD
Post by: GeoffB17 on 00:25, 22 January 23
Regarding my last message, I've just tried to format another disk as CF2DD (Amsoft/Panasonic) and this one has formatted and then verified perfectly.

So I'm now scoring 2/4!

The disks that were used for the system disks are usually the Panasonic ones (with the hash grid, and the big white write protect tabs) so I've tended to assume these are slightly better, while the Maxell ones (plain surface, small red lever type w/p tabs) have seemed almost as reliable.  But one each has failed.  And one of each has passed!

Nothing conclusive yet.

Geoff
Title: Re: Use CF2 as CF2DD
Post by: Audronic on 00:37, 22 January 23
@GeoffB17 

You can try Bulk Erasing the disk with a Magnet
Please try by rubbing the magnet over the disk cover and the "IMPORTANT" slowly move the magnet away while still moving the magnet.
I  Have found that this will release any " Stuck " areas of the disk with high flux areas.
and May allow you to Reformat the Disk

Good luck

Keep Safe

Ray
Title: Re: Use CF2 as CF2DD
Post by: GeoffB17 on 01:02, 22 January 23
Ray,

Thanks.

That's pretty much what I've always done.  I've had disks (3", 3.5", 5.25") that were otherwise perfect that would not format, prob due to previous formats/data writes that were slightly out of alignment, and the magnet treatment has resulted in a successful format, and perfect operation ever since (well, until someone has messed up the disk again...).

Geoff
Title: Re: Use CF2 as CF2DD
Post by: GUNHED on 21:20, 22 January 23
Quote from: Audronic on 22:18, 21 January 23
Quote from: GUNHED on 17:00, 21 January 23Never use a magnet please! There's a bunch of reasons, but I'm not going into detail, because I have no time for discussions.
Hi Gunhed

---  WHY ---

Keep Safe

Ray
Greetings Ray,

Well, I try to explain... In case the magnet is weaker compared to the magnetic field of the floppy write head, then it won't change much.
But in case the magnet is stronger, then the floppy head my not have to write data on the disc, because the magnetification level of the disc is too high, so data can't be written properly. Magneto can explain better...  ;) :) :) :)
Title: Re: Use CF2 as CF2DD
Post by: GUNHED on 21:21, 22 January 23
Quote from: GeoffB17 on 00:25, 22 January 23The disks that were used for the system disks are usually the Panasonic ones (with the hash grid, and the big white write protect tabs) so I've tended to assume these are slightly better, while the Maxell ones (plain surface, small red lever type w/p tabs) have seemed almost as reliable.  But one each has failed.  And one of each has passed!
Can only support your findings. I prefer Panasonic discs too. 
Title: Re: Use CF2 as CF2DD
Post by: GeoffB17 on 23:35, 22 January 23
Well, regarding message last but one above, I suppose there MIGHT be a point there, but I've never had a magnet THAT powerful. and I don't think I ever will.   The magnets I've used are just normal domestic types, and they must be well within the range that works fine, i.e. enough magnetism to clean the disk (or at least weaken what was there so it doesn't cause any problem), and not too powerful - although I doubt that the magnetic capacity of the surface of the disk could retain enough magnetism for this to happen?

However, you said there was 'a bunch' of reasons, what are the others?

Geoff
Title: Re: Use CF2 as CF2DD
Post by: Audronic on 00:10, 23 January 23
Quote from: GUNHED on 21:20, 22 January 23
Quote from: Audronic on 22:18, 21 January 23
Quote from: GUNHED on 17:00, 21 January 23Never use a magnet please! There's a bunch of reasons, but I'm not going into detail, because I have no time for discussions.
Hi Gunhed

---  WHY ---

Keep Safe

Ray
Greetings Ray,

Well, I try to explain... In case the magnet is weaker compared to the magnetic field of the floppy write head, then it won't change much.
But in case the magnet is stronger, then the floppy head my not have to write data on the disc, because the magnetification level of the disc is too high, so data can't be written properly. Magneto can explain better...  ;) :) :) :)
Ok I have read what you sent.

That is the reason for slowly moving the Magnet away from the disk while still moving it around to decrease the affect of the magnet on the media. 
We are trying to demagnetise " Stuck Bits " of flux on the disk.
This principle is used in Professional Bulk erasers, where I worked for some 30 + Years.

Thanks for you thoughts

Keep Safe

Ray
Title: Re: Use CF2 as CF2DD
Post by: GUNHED on 14:16, 24 January 23
Quote from: Audronic on 00:10, 23 January 23
Quote from: GUNHED on 21:20, 22 January 23
Quote from: Audronic on 22:18, 21 January 23
Quote from: GUNHED on 17:00, 21 January 23Never use a magnet please! There's a bunch of reasons, but I'm not going into detail, because I have no time for discussions.
Hi Gunhed

---  WHY ---

Keep Safe

Ray
Greetings Ray,

Well, I try to explain... In case the magnet is weaker compared to the magnetic field of the floppy write head, then it won't change much.
But in case the magnet is stronger, then the floppy head my not have to write data on the disc, because the magnetification level of the disc is too high, so data can't be written properly. Magneto can explain better...  ;) :) :) :)
Ok I have read what you sent.

That is the reason for slowly moving the Magnet away from the disk while still moving it around to decrease the affect of the magnet on the media.
We are trying to demagnetise " Stuck Bits " of flux on the disk.
This principle is used in Professional Bulk erasers, where I worked for some 30 + Years.

Thanks for you thoughts

Keep Safe

Ray
Sounds very interesting - and possible. But I guess it would take a machine to do this or somebody who has the magnetic lines in mind to weaken the magnetic imprint as you explained it.  :)
Title: Re: Use CF2 as CF2DD
Post by: pelrun on 15:49, 24 January 23
That machine is called "electric drill with a magnet taped to the end".

Unfortunately such things are not available except in high end laboratories. :laugh:
Title: Re: Use CF2 as CF2DD
Post by: GeoffB17 on 21:01, 26 January 23
All,

Please note that my original questions still stand.

Please disregard detours regarding magnets.

Geoff
Title: Re: Use CF2 as CF2DD
Post by: GeoffB17 on 20:50, 01 March 23
Not had chance to try any more CF2 disks for a while, but I've just done another.

This was a fairly old, well used disk, although clean etc.  Label written on a fair bit, another label stuck on top, more writing on that.   Used magnet to ensure well wiped.

Ran format.   There was a problem about Tr 1 (where the directory would have been, but had chance to pop disk out, give it a little shake, re-insert, said to retry, and it proceeded, and completed the full disk.   Did an immed Verify, all OK.

Disk was an old-style Panasonic branded one.   Not the later (?) silver/black label with the 'Panasonic' name, this one has some yellow/red bands, and no 'Panasonic'.  I've come by a few others, similar.

So I'm now 3 of 5 have formatted OK, so the percentage is improving!

There were some Amsoft CF2-DD on ebay recenty, I tried to bid but couldn't connect, and then the auction ended.  Something funny happening there??

Geoff
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