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Re: Adding a second floppy drive to an Apple IIe

Jeff Shanholtz wrote:

Well, I'm having second thoughts and may want to revive one of these
after all. 2 of the drives are off brand and 1 is apple so I'm hoping
to get the apple one working. It does spin up at boot time and I hear
the familiar booting sound coming from the drive, but at that point it
just spins without any hint of real activity (with a bootable disk in,
of course). Are there any troubleshooting guides available somewhere
to help me fix this? I do have hardware repair experience but I
wouldn't know where to start looking, and I'm guessing someone has
compiled a document somewhere about restoring these things.

These symptoms don't strike me as being explained by one of the
mechanical problems described by you, Michael, but if you disagree I
would be happy to crack her open and have a look.

I appreciate the advice!


Dave is right, a blown 74LS125 will disable the read channel (among
other things), and a drive that turns on and seeks, then just spins
(with a good bootable disk) is a sign of no read signal.

If it isn't the '125, it could be a dirty head, misalignment (not
likely unless a drive has been dropped), a bad analog board, or
a bad cable.

With a 'scope you can trace the read signal and see where it's
getting lost.  Or you can swap known good components to isolate
the problem (always with some possible risk of damaging a good
component in the process).


On Apr 29, 4:55 pm, "Michael J. Mahon" <mjma...@aol.com> wrote:


Jeff Shanholtz wrote:


Thanks guys. These drives were borrowed from a friend and I was
possibly going to buy one, so I will likely just give them back as
they are. I'm sure I plugged them in correctly though.


Old drives often have "mechanical" problems:

1. Off-speed--run speed adjusting program and adjust speed pot.
2. Dirty head--open and clean head carefully with alcohol.
3. Congealed seek cam grease--open, clean old grease, and
   sparsely regrease with lithium grease.  Also check head guides.
4. Hardened drive belt--open drive and inspect belt.  Replace if
   hardened, "exercise" it if it just has a "set".  Speed may need
   adjusting.  (Occasional use prevents/cures some belt problems.)


-michael

NadaNet 3.1 for Apple II parallel computing!
Home page:  http://home.comcast.net/~mjmahon/

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