Apple II Floppy Diskettes

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 001- How many tracks can I use on a 5.25" diskette? 
 002- Can I use high-density 3.5" and 5.25" diskettes on my A2? 
 003- How can I tell DD from HD diskettes if they are not labeled?
 004- Some old 5.25" disks with splotches don't boot. What gives? 
 005- How can I defragment a diskette and what is the speed gain?
 006- Why aren't my old diskettes recognized by GS/OS?
 007- Can I read Apple II diskettes on my PC?
 008- Where the heck can I buy double density 3.5" & 5.25" diskettes?

From: Rubywand

001- How many tracks can I use on a 5.25" diskette? So far,
     I've heard 35, 36, and 40. What's the actual number?

     The standard number of tracks on a 5.25" diskette is set by DOS 3.3
and ProDOS at 35, numbered 0-34 ($00-$22 in hexadecimal).

     The original Disk ][ drive can usually handle 36 tracks with no
problem. Newer 5.25" drives can handle 40 tracks.

     Various modified versions of DOS 3.3 allow using 36 tracks and a
few allow using 40 tracks. These mods, especially the 36-track versions,
were fairly popular before the advent of 3.5" diskettes when an extra
track made a noticable difference in capacity. However, unless the extra
capacity is vital for some specific application, it is best to stick
with 35 tracks in order to retain full compatibility with disk utilities
(such as Copy II Plus) and other wares.


002- Can I use high-density 3.5" and 5.25" diskettes
     on my Apple II?

     I did some magnetization tests on Double Density (800kB) and High
Density (1.4MB) diskette surfaces. The tested DD surface produced more
than twice the deflection of the tested HD surface. Clearly, there is a
big difference in signal levels required to reliably store data on HD
vs. DD.

     In fact, 5.25" HD (1.2MB) diskettes will not work at all on Apple
Disk ][ drives. The 3.5" HD's may work fine on your 800k drives; or,
they may just seem to work fine. Either way, there's no question: a
drive optimized for DD will not be optimized for HD. If you'd rather not
'roll the dice' on your software collection, stick with Double Density


003- How can I tell the difference between unlabeled
     DD and HD diskettes?

     3.5" HD (1.4MB) diskettes come with a square notch in the upper
left corner. DD (800kB) 3.5" diskettes do not come with this notch. In
the early days of PC computing, some PC users punched or drilled notch
holes in DD diskettes and used them as HD diskettes. If a 3.5" diskette
has a circular notch in the upper left corner, it is likely to be a DD

     DD 5.25" (360kB) diskettes look very much like HD 5.25" (1.2MB)
diskettes. About the only remotely observable difference is that DD
diskette surfaces often exhibit a more brownish cast whereas HD diskette
surfaces are generally dark grey or black.

     The surest test for 5.25" diskettes is to place the diskette into
an Apple II 5.25" drive and try to do a DOS 3.3 format. If it formats
with no problem, it is almost certainly a DD diskette.


004- Recently I found that some of my old 5.25" disks would
     not boot. A check showed splotches etched on the surface
     of the media. What's going on?

     As you may recall, a number of the classier 5.25" diskette brands
employed (still employ?) a lubricant on their jacket liners. While the
lube worked to reduce drag and noise, it also, evidently, served as a
growth medium for a particularly nasty plastic and/or oxide-eating

     It's probably a good idea to check each of your old diskettes.
Immediately backup any diskettes with splotchy discolorations.


005- How can I defragment a diskette and what is the speed gain?

     You can defragment a diskette by doing a File Copy of all files to
a blank diskette or blank RAM disk. Files on the copy diskette or RAM
disk will be almost completely unfragmented. A whole-disk copy back to
the original completes the process. Tests show that this method produces
much speedier diskettes than using a utility intended for optimizing
hard disks.

     For a nearly full 'workhorse' diskette which has seen may deletions
and additions, you can expect the File Copy defragmentation method to
yield a 30% to 40% improvement in access speed. 


006- Why aren't my MECC and many other old diskettes recognized
     by GS/OS and mounted on the Finder display?

     The problem you mention is fairly common. GS/OS via its FSTs has
pretty strict definitions for what qualifies as a valid DOS or ProDOS
diskette. For example, perfectly good 36-track DOS 3.3 diskettes will
not be mounted by the Finder just because the number of tracks is 36
instead of the expected 35.      

     Naturally, copy-protected diskettes have practically no chance of
being recognized. Almost certainly, this is the reason the Finder will
not mount your MECC disks.

     You can, still, run software from most copy-protected diskettes by
just booting them.


From: Chris Norley

007- Can I read Apple II diskettes on my PC?

     A while back I requested some information regarding the reading of
Apple II floppies by an PC. There was a hugh response both in solutions
and requests for a summary of solutions.


     We have some old data from a small NMR spectrometer that was run
from an Apple IIe. The same spectrometer is now run from a DOS machine
and we'd like to be able to access the old data from the PC.

     Does anyone know of or possess some utility to allow the data from
the 5 1/4" Apple II floppies to be read from the PC? Any hints as to
program names, ftp sites, etc. would be greatly appreciated.


From news ...

Les Ferch

It can't be done with software alone. There is a card called the
MatchPoint PC card that will let you read and write Apple II DOS,
ProDOS, and CP/M disks on a PC 5.25" 360K drive. We used to have one
installed in an XT here and it worked fine.

The other common way of moving the data is to connect an Apple II to a
PC using a null modem cable and using comm programs such as Kermit to
transfer the data.


Curt Schroeder

It is not possible for a 5.25" PC floppy drive to read Apple II disks. 
They use incompatible recording technologies.  Your options are to get
your data into an Apple that can write MS-DOS 3.5" disks (Apple IIgs or
Macintosh) or transfer via serial link (either via modem or null-modem
cable).  The other possibility is to use an Apple II equipped with a PC
Transporter and either has a 3.5" drive or 5.25" PC floppy drive(s)


Michael Hoffberg

About a year ago, I picked up card for my ibm made by TrackStar.  It is
basically an apple II that sits inside your IBM.  When you enable it, it
can boot off an apple drive, it uses the ibm keyboard and monitor.

When I go home I only use it to play moon patrol (I am too lazy to find
my other games).

In any case, I think that it is possible to transfer files between the
ibm and apple with the card.  I have never tried it though.


Fred R. Opperdoes

Any Apple II (E or GS) owner having an Applied Engineering PC card is
able to do the job easily. It is maybe not easy to find such a person in
your neighborhood. Another possibility would be that you ask someone
with an Apple IIGS to have your 5 1/4" Dos 3.3 or Prodos disk
transcribed to a 3.5" Prodos disk. Every IIGS owner would be able to do
so. Files on such disks can then easily be converted to MsDOS files on
an MsDOS disk on a Macintosh using the Apple File Exchange Utility that
comes with every modern Mac.


Leo Connolly

I don't think this is doable.  There are limitations in the PC drive
hardware which make it impossible to read Apple II disks.  (And the same
is true in reverse, for exactly the same reasons).

I suggest the following.

Transfer the Apple II data to a 3.5" disk.  This is easy on a IIGS if
you use a utility such as Copy II Plus.

Use Apple File Convert on a Macintosh to convert the Apple II files to
MS-DOS format.  Caution: older versions of this utility cannot handle
MS-DOS 3.5" disks, but the newer ones can.

Or: send your data through a modem from the Apple to the PC.


Leonard Erickson

It can't be done without extra hardware. The Apple II didn't use a disk
controller chip, it used an odd circuit instead. So, machines using the
industry standard controller chips can't read Apple disks.

You'll need a COPYIIPC deluxe option board or some such. Check with
Central Point software, they used to sell them.

Another approach is to track down one of the add-on boards that was
essentially an Apple II on a PC card. It hooks to the 5.25" drive and
plugs into the bus. And you've got an Apple II in your PC.


The cheapest method to get the data would to do a "NULL MODEM" transfer
between the two computers.


From: Rubywand

008- I'm having a hell of a time tracking down a place to buy
     double density 3-1/2 & 5-1/4 disks. Any suggestions?

     Here are a few places to try ...


     Until very recently, Alltech (760-724-2404) advertised DS-DD 5.25"
disketts for $15/100 with sleeves + shipping. Their price for DD 3.5"
diskettes was pretty good, too. Alltech has done a major revision of
their web page which seems to omit many favorite items; but, although
diskettes are no longer listed, they may still sell them.

Midwestern Diskette

     A few months ago, I was noticing the problem with finding places to
get 5.25" DS-DD diskettes. I did not know about Alltech's offer and
ended up buying from Midwestern Diskette (800-221-6332). They offered
the diskettes in several colors at a good price; so, I bought 500
diskettes in five colors. Actual price was $17/100 for color diskettes
with sleeves and labels and shipping. I think Midwestern also sells DD
3.5" diskettes.

Note: One oddity I've discovered is that some colors (from Midwestern
Diskette) do not accept notching (for using the back) as well as others.
There has been no problem notching White, Lavender, Yellow, and Green.
However, the Orange diskettes are too brittle to allow a clean square
notch-- they can be punched using a round hole punch.

Thrift shops

     Brian Hammack reports finding packs of used 5.25" diskettes at
bargain prices.