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-   -   Opinions on using HD floppy diskettes on classic Amiga (https://eab.abime.net/showthread.php?t=81775)

turrican9 28 February 2016 21:50

Opinions on using HD floppy diskettes on classic Amiga
 
So I read some people claiming the 1.44MB HD diskettes are less reliable VS DD diskettes when formatted to 880KB Amiga format. So anyone have any proof of this?

Reason I ask is because I'm starting to build up my floppy collection. And have alot of old PC HD 1.44MB diskettes. I use X-Copy PRO with wb format and Validate. Of course many of the old disks are damaged (Over a 100 thus far) but have managed to format about 180 Amiga DD diskettes and about 40 PC HD diskettes with validate and no errors. So now I have about 100 + more HD diskettes to check and format.

ajk 28 February 2016 22:09

Well, there is certainly a clear technical difference between the two: high density disks use a different kind of magnetic coating. A double-density drive won't necessarily be able to write the signal onto the disk as well.

In practice it works okay, sometimes even for long periods of time. There are so many specific types of drives and floppies that all you are going to find is anecdotal evidence either way.

Daedalus 28 February 2016 22:23

Many people report that they format fine but they don't retain their data as long as genuine DD disks. The theory makes sense (HD media need a higher field strength from the heads than DD media), but I've yet to see proof of it...

As an experiment, I've dug out a few floppies that were supplied on HD disks with the hole filled in (hard drive prep disks from Wizard Developments in 1997 or so). They haven't been touched since then, and I've tried two of them in my A1200 and both read 100% perfectly. So they're probably safe for a few years anyway...

turrican9 28 February 2016 22:25

Quote:

Originally Posted by ajk (Post 1073991)
Well, there is certainly a clear technical difference between the two: high density disks use a different kind of magnetic coating. A double-density drive won't necessarily be able to write the signal onto the disk as well.

In practice it works okay, sometimes even for long periods of time. There are so many specific types of drives and floppies that all you are going to find is anecdotal evidence either way.

Thanks for the answer. I have written a few ADFs to HD disks and it seemed to work fine. I just wonder how reliable they will be. Will probably just have to test see what happens long term. All my disk drives are original Amiga ones.

Quote:

Originally Posted by Daedalus (Post 1073993)
Many people report that they format fine but they don't retain their data as long as genuine DD disks. The theory makes sense (HD media need a higher field strength from the heads than DD media), but I've yet to see proof of it...

As an experiment, I've dug out a few floppies that were supplied on HD disks with the hold filled in (hard drive prep disks from Wizard Developments in 1997 or so). They haven't been touched since then, and I've tried two of them in my A1200 and both read 100% perfectly. So they're probably safe for a few years anyway...

Thanks for the answer. So that's 19 years in storage and still working

ajk 29 February 2016 06:03

Just make sure that your only copy of anything isn't relying on a floppy. You can always recreate the floppy from an image file if it goes bad, so it shouldn't be a huge issue.

Also taping over the HD hole does not matter when using genuine Amiga drives, since they don't have a sensor for it anyway. But you do need to do it if you want to fool a HD drive into thinking you are using a DD floppy.

alexh 29 February 2016 07:04

My opinion is they work fine in either direction. I've got HD disks written as DD from 20 years ago which still work and vice versa. I used to drill holes in my previously used on Amiga DD disks so they cold be used with my HD super magicom. Good proportion of both disks still work today.

jbenam 29 February 2016 10:39

I've had some HDs fail on me after a few months with read errors and such, while I still have a bunch of them from the 90s which work fine. So it's pretty random, really.

What I do _definitely_ remember though, was how so many games would just "stop working" for no reason at all when I was a kid... Pretty sure it was due to HD floppies, I just didn't know that back then ;)

Jope 29 February 2016 12:26

Take some neodymiums and wipe around the HD disk with those before writing, that way the DD write current doesn't have to fight against a pre-existing HD track that might be written with a different alignment and you'll probably get better results.

The difference in coercivity between 3.5" HD vs DD is a lot less severe than in 5.25", only around 720oe for HD and 650oe for DD, so it is much more probable that you can use HD media in a DD drive with success.

5.25" is different though, there you should never use HD media in a DD drive (such as the 1541). I have enough anecdotal evidence to support this, having dumped thousands of scene floppies in my time. 1541 written HD floppies are always full of errors these days, but real DDs read quite well even after all these years.

Cobe 29 February 2016 13:41

Back in 90s with new A1200 I didn't have problems neither with DD nor with HD disks. Today with A500 and A600 I have problems with both types.

turrican9 29 February 2016 14:11

Quote:

Originally Posted by Cobe (Post 1074131)
Back in 90s with new A1200 I didn't have problems neither with DD nor with HD disks. Today with A500 and A600 I have problems with both types.

Maybe it's because of the age of the diskettes?

rockape 29 February 2016 14:14

Hi turrican9,

See A1200 Hardware Frequently Asked Questions

http://www.wonkity.com/~wblock/a1200/a1200.html

Q. Can I use high-density floppies with the A1200's normal disk drive?

A. Not reliably! The high-density disks need a stronger magnetic field from the disk heads to reliably write to them. A high-density drive does this automatically, but the A1200's double-density drive can't.

Writing high-density disks with a double-density drive will result in erratic operation of those disks.

They may work fine for hours, days, or weeks, only to fail when you need them most. Use double-density disks with Amiga double-density (880K) drives, like the one built into the A1200, or get an external or internal high-density Amiga drive."

So it's up to you.

Also.

Ive noticed that AmigaKit send software on HD Disks now.


Regards, Michael

aka rockape

Cobe 29 February 2016 15:06

Quote:

Originally Posted by turrican9 (Post 1074134)
Maybe it's because of the age of the diskettes?

Exactly. That's my opinion. Simply:
new drive + new diskettes(HD/DD) = no problems
old drive + old diskettes(HD/DD) = problems

Daedalus 29 February 2016 16:28

Quote:

Originally Posted by rockape (Post 1074135)
Ive noticed that AmigaKit send software on HD Disks now.

Yep, it must be getting pretty tricky to find a reliable supply of DD disks these days, especially when you consider that Wizard Developments were shipping software on HD disks in 1997...

turrican9 29 February 2016 16:35

Well, one thing is for certain, there is no future in floppy diskettes. I have whdload setups and floppy emulators, but I still like to use floppy diskettes for nostalgia. I just love to load up a floppy game and hear the sound of the drive. I have now ordered 50 DD diskettes on ebay. If all these are working with no errors, like the seller states, then I will have about 220 working DD diskettes. Should last me quite some time.

Edit: I will try to write games to a bunch of HD diskettes to test logevity on them. I'm very curious how long they will last.

Amiga1992 29 February 2016 17:51

Quote:

Originally Posted by Jope (Post 1074113)
Take some neodymiums and wipe around the HD disk with those before writing, that way the DD write current doesn't have to fight against a pre-existing HD track that might be written with a different alignment and you'll probably get better results.

Never heard this tip, thanks!
Do you think you could do the same with DD disks that are giving trouble formatting?

As a general rule I avoid HD disks, they last a lot less.I guess the higher density makes them less reliable.

Jope 29 February 2016 20:22

Yes, you can sometimes fix unformattable disks with magnets. :-)

I remember having to do it many times in the PC era, where format.com happily reported "unable to format track 0, format aborted".. A few wipes with a magnet later and it usually formatted the disk without trouble. :-D

I have so many DD disks that I'll never run out, others may not be so lucky. I tried offering some for sale at one point, but people seemed to want them certified working and for free, so I decided it wasn't worth my while. :-D

turrican9 29 February 2016 21:20

Well. Now I have 194 DD disks formatted with WB format Verify enabled in X-Copy PRO and also used checkdisk with verify on all these. When I get the 50 from ebay I will have a total of 244 fully working DD diskettes (Assuming those from ebay are 100% working like the seller states). I also have about 150 HD disks where I have formatted and verified 40 of them thus far that check out okay. I will try to avoid using the HD disks and just stick to my DD diskettes. 244 will be plenty for my needs. But as I said, I may test a few HD disks just to see how long they will last after I write games to them.

Edit: The 50 DD disks I ordered was from an Atari seller. They are DOS formatted but still DD disks. I hope it does not matter if they have been DOS formatted. Of course I will use X-copy to reformat them when I get them. btw, just sitting and using X-copy hour after hour is just awesome. X-copy actually is fun and very nostalgic. Who didn't use it back in the day? ;)

Quote:

Originally Posted by Jope (Post 1074225)

I have so many DD disks that I'll never run out, others may not be so lucky. I tried offering some for sale at one point, but people seemed to want them certified working and for free, so I decided it wasn't worth my while. :-D

I may be interested in buying 100 DD diskettes from you at some point. If you can spare that many for a Norwegian fellow

john1979 29 February 2016 21:39

Quote:

Originally Posted by Daedalus (Post 1073993)
Many people report that they format fine but they don't retain their data as long as genuine DD disks. The theory makes sense (HD media need a higher field strength from the heads than DD media), but I've yet to see proof of it...

That's actually been my experience. They appear to work great for a while then fail quite randomly. Some after a few hours, others months. I find DD floppies on the whole more reliable with the Amiga.

turrican9 29 February 2016 21:43

Quote:

Originally Posted by john1979 (Post 1074241)
That's actually been my experience. They appear to work great for a while then fail quite randomly. Some after a few hours, others months. I find DD floppies on the whole more reliable with the Amiga.

Did they just loose the data so you could just write them again, or did they generate errors?

john1979 29 February 2016 22:21

Quote:

Originally Posted by turrican9 (Post 1074243)
Did they just loose the data so you could just write them again, or did they generate errors?

Most of them seemed to generate errors and wouldn't be written to again. I had a few that would format okay after failing though too.


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