• Updated 2023-07-12: Hello, Guest! Welcome back, and be sure to check out this follow-up post about our outage a week or so ago.

30MB Miniscribe Hard Drive from Mac SE -- reads data, but cannot be written to!

RedJacketPress

Well-known member
I've been tinkering with and restoring a Mac SE (with two Floppy Drives and a 30MB Hard Drive) -- I got to the point where I wanted to erase the Hard Drive and reinstall (not my data, and the computer will eventually be offered for sale), but I have been unable to format the drive!

I've tried several different utilities -- sometimes I'll get an error (usually during an attempt to verify), sometimes I'll get no error at all, and it's as though the process has successfully completed. Sometimes the drive will be unmounted and I won't be able to get it back. But once I restart -- there it is, data and all!

I've also tried manually moving files off to the Trash -- that isn't working, either (can't empty the trash!), and I can't even save any preferences that might want to write to the Hard Drive.

It seems obvious I can read from (and even boot from!) the Hard Drive, but I can't write to it. Do these Hard Drives have separate Read and Write Heads?
 

Nixontheknight

Well-known member
I've been tinkering with and restoring a Mac SE (with two Floppy Drives and a 30MB Hard Drive) -- I got to the point where I wanted to erase the Hard Drive and reinstall (not my data, and the computer will eventually be offered for sale), but I have been unable to format the drive!

I've tried several different utilities -- sometimes I'll get an error (usually during an attempt to verify), sometimes I'll get no error at all, and it's as though the process has successfully completed. Sometimes the drive will be unmounted and I won't be able to get it back. But once I restart -- there it is, data and all!

I've also tried manually moving files off to the Trash -- that isn't working, either (can't empty the trash!), and I can't even save any preferences that might want to write to the Hard Drive.

It seems obvious I can read from (and even boot from!) the Hard Drive, but I can't write to it. Do these Hard Drives have separate Read and Write Heads?
I don't think so, have you tried formatting the disk on a different machine?
 

RedJacketPress

Well-known member
I didn't think so, either -- this is why it seems like such a strange symptom.

I did try this on a second Mac SE, with the same results. One of the pieces of software suggested it may have been locked by a third party tool, though that seems as though it would kind of get in the way of using the computer day-to-day (it hadn't been set up as a kiosk, or anything like that).
 

techknight

Well-known member
Is this a miniscribe drive? I have seen the write amps fail on these drives in the past. Entirely possible thats what happened. The head isnt getting the write current from the write amplifier IC.
 
Top