IBM 4869 5.25" floppy drive

From: Jason Willgruber <roblwill_at_usaor.net>
Date: Mon Sep 14 16:43:27 1998

>
> The other week I bought an IBM 4869 5.25" floppy drive. This is an
external
> unit that hooks up to a PC via a 37-way D connector. The case is massive,
for a
> simple floppy drive.
>
The extra space (length) is the power supply. I also have one of those
drives.

> Anyway, I can't get it to work properly. It is probably a 360K drive
mechanism,
> and my PC (Philips 386SX AT clone) boots normally with this type of drive
set
> in the backup RAM.

It was made to work with the XT, plugging into a special port on the disk
controller card. Yes, it is a standard 360K drive.

>
> I can format disks and use DIR, but reading or writing any files always
gives
> an Abort/Retry/Cancel error. Unsurprisingly, cleaning the heads made no
> difference. Actually, to elaborate on this copying a load of files to a
newly-
> formatted disk gives an error after copying (say) the first two files.
>
> Does this drive have some non-standard pinout, different from the 37-way
D
> 5.25" port on the back of the PC, or maybe only work with IBM PS/2
machines?
>
The D connector goes directly to the disk drive.

> If it is just faulty, what might the problem be? The cable is unlikely I
think,
> as is the power supply.
>
> The casing has a couple of tamperproof Torx screws. I'd like to know what
size
> they are so that I can buy a suitable screwdriver bit.

Tamperproof screw solution: a SHARP 1/2" drill bit. Just drill off the
heads, and you'll have no problem.

The drive that I had, I had no use for, and couldn't get it to work with my
PC, so here's what I did:

-Pulled the old 360K drive, and replaced it with a 1.2 meg drive.
-Cut a hole in the top of the case large enough so that I could attach a
3.5" drive on top of the 5.25".
-Super-glued the 3.5" to the 5.25" drive.
-Split the power cable, and put a 3.5" floppy connector on it so that the
P/S could power both drives.
-Using a TRS-80 printer cable (ribbon - type), I twisted the cable and put
on new plugs to connect the floppies.
-Ran the ribbon cable under the P/S, and out a slot that I cut in the back.
 
-Connected all cables, and put the case back together.
-Ran ribbon cable into open slot on back of computer and connected to
floppy connector.

It may seem like a bit of work to get an external drive, but it sure beats
buying a new $80 tower case.
--
         -Jason
(roblwill_at_usaor.net)
   ICQ#-1730318
Received on Mon Sep 14 1998 - 16:43:27 BST