1.44 MB floppys used in 880K Amiga Disk Drives

I'm still curious about the above statement that the use of HD disks will damage the DD drive in an Amiga. Personally, I do not care if my floppies all die 3 seconds after I take them out of the drive - to me they are only for moving files from my PC to the Amiga, so if they become useless after accomplishing that, it's ok. However, if the heads in my drive are going to be damaged, that's another story. I have never heard of this problem before; has anyone here actually damaged a drive this way?

[klx300r]

orange wrote:
@rkauer, @weirdami

thats not true, at least some DD drives do have HD sensor. I know my A500 original drive has it.

the problem is that such diskettes are not reliable, in a few hours or days they might become unreadable.

hmm well Ive been using HD disks with my 1581 dating back 1991 and not even one bad block has been noticed! ironically brand new DD's used on both my miggy and 64/128 systems have failed on me after only a few months of use :-?

[Damion]

I've used HD floppies with "OK" results, they work but I've found there are more instances of errors, disks that need to be written to twice, etc.

Where as the DS/DD disks from 15+ years ago (stored in the same boxes) STILL have 90% or more readable.

I fired up a bunch of my old Amiga floppies a few weeks back, and fortunately, most of them seem to be fine as well. (The C64 disks were OK as of about 3 years ago.) I picked up a bunch of (unwanted) floppies recently, they were stored properly but came from a humid environment. Interestingly, about 50% of the ones I tried were junk, couldn't even be formatted without errors.

BTW -- If anyone needs a good source for DD floppies, the Diskette Connection are a great bunch to deal with. (The Imation brand floppies they sell are made in the US, which is kind of cool to see these days.)

[amigadave]

@-D-,

Diskette Connection is sold out for DD diskettes.

[Fester]

weirdami wrote:
One thing you could try is drilling a hole in a DD disk and seeing if it will work in an HD drive. I remember people trying that a long time ago. Dunno what the results were.

I used to do that in college to save money. I'd stack the DDs on a 2x4 and drill'em. Never had a problem.

[amiga_3k]

IIRC the A1200s from ESCOM/AmigaTechnologies actually used modified HD PC-drives as DD Amiga drives. In those machines, taping of the hole was needed to use HD floppies as DD.

I never had any problems with HD floppies used as DD. Must state that I always bought No-brand floppies (cheap dutch guy :-)).

[Damion]

amigadave wrote:
@-D-,

Diskette Connection is sold out for DD diskettes.

Ah, bum deal. I ordered a few boxes some months back, "just in case" I'd need a few someday. Maybe they'll get more in.

[Zac67]

Since the early 90s DD and HD floppies were made with the exact same media inside.

But: once these get written to with a HD drive (e.g. PC preformatted) they may be troublesome in DD drives. According to several experts, HD heads write 'harder' bits that are just overlayed with the 'softer' DD bits. The DD bits deteriorate faster than the harder HD ones and practically get overwritten from underneath. This effect depends largely on the exact specs of the media used (which we usually know nothing of).

I can't confirm this from my own experience though (been using an Amiga HD drive for the last 15 years), but for valuable data it's definitely worth considering. Actually I don't trust floppies further than I can throw them...

[orange]

HD heads write 'harder' bits that are just overlayed with the 'softer' DD bits.

hmm, thats interesting.. so would this help:
-cover the hole and format it on PC as 720Kb,
-reformat on Amiga ?

[Tricky]

I realised a few years back that most cheap floppy drives on PCs these days don't even have the DD/HD hole detection switch!  They can't read or write DD disks at all because of this.  I had to replace the floppy drive in my PC with an older one in order to transfer things to and from my Amiga.

I've always used Sony HD floppies on my Amiga, and they seem to work fine.  Apparently, there is some overlap in the specification in the range of field strength required for HD/DD, and Sony disks tend to be in the overlap.  I can't remember where I read that now.

I don't even have a regular pc with a floppy drive at all; some years ago I needed to make a sata driver disk for a win xp install on a friend's machine, so I picked up a teac usb floppy drive for cheap. it's great because I've gone through 4 generations of computers since and I don't have to worry about transplanting a drive or buying new ones. (i've noticed that floppy drives tend to have a greater lifespan if they're not in the system case having dirty air blown at them by the cooling fans.) the drive, btw, definitely has the HD sensor.

I used to find that I could never rely on floppy discs marked with a brand name to have been manufactured in a consistent manner - I would buy them in boxes of 100 and noticed that the batches had remarkably different failure rates, so now I always buy my discs from radio shack because they're cheap and I never saw any correlation between cost and the discs' quality.

[Methanoid]

Thread resurrection time;

What about the 1.76FDD in the A4000. Is that "safe" to use with 1.44Mb HD floppies but to format them as 880K for games etc?

[psxphill]

Since the early 90s DD and HD floppies were made with the exact same media inside.

That is not true.
 
http://www.retrotechnology.com/herbs_stuff/guzis.html

[Zac67]

HD drives can handle/overwrite 'harder' bits, so they should be fine with HD floppies whether in HD mode or not. Actually, any DD floppy ever written to in a HD drive and then rewritten in a DD drive can be a problem over time... (I don't know whether HD drives vary the write current according to the currently used density but the write field from a HD head will always be denser.)

I guess the effect largely varies with the different media types. Additionally, many late DD drives are probably using HD heads anyway, so you may or may not notice bit rot over time - but you've been warned.

[spaceman88]

Thread resurrection time;

What about the 1.76FDD in the A4000. Is that "safe" to use with 1.44Mb HD floppies but to format them as 880K for games etc?

Should be OK as long as you cover the "extra" hole, otherwise it will try to read it as a 1.76mb disk.

[kedawa]

I modded my old PC's floppy drive with a switch that let me use old DD disks as HD disks, and never once had a problem with them.
I think if you have quality disks, they'll work fine regardless.