On 02/13/2013 10:27 AM, Scott Quinn wrote:
I have a 3B2/1000 that I'm trying to resurrect.
The main Winchester
drive is dead-ish (haven't written it off, but it's doing
spinup-click-spindown so there's something big wrong), so I need to
label a new drive.
3B2s are DSQD floppies, and I'm trying to figure out my best
approach. I have the utility software in a disk image, but PCs
usually don't ship with DSQD drives. I've found three possible
options, but don't know if anyone's used any of them (or one that I
haven't come across).
(1) Mount the 3B2's DSQD floppy in a PC and try to write out the disk
using it. Don't know if the PC's disk controller supports DSQD- I
have a Compaq Deskpro 386/25 and a whitebox Pentium that I can try
(2) modify one of the above machine's stock 1.2MB drives to spin at
300RPM. Don't know if it will write out the disk this way, but found
mod. instructions here:
http://www.oldskool.org/disk2fdi/525HDMOD.htm
. May work, may not -I'm not sure how QD and HD head widths compare.
(3) Replace the 3B2's 5.25 DSQD drive with a 3.5" drive and use 720K
3.5" disks to load it. Don't know how well 3B2 hardware would like
this mod.
I do have the proper DSDD media to use, so that's not an issue. I'd
probably write the disk out with "dd" on Linux or xBSD if possble, as
the network support makes getting the image to the writing machine
much easier.
Anyone been in this position before?
What are you using for imaging software? Most should work with a plain
old unmodified "1.2M" drive in a PC AT or better (the controller uses a
300KHz data clock instead of a 250KHz one when handling DD floppies).
Most imaging software is aware of this and adjusts accordingly. It's
true that if the software uses the BIOS, the drive will double-step, but
that's not true if the software uses its own floppy code.
You're making the job too difficult for yourself, I think.
--Chuck