John Wilson wrote:
On Thu, Jan 24,
2013 at 11:53:47PM -0700, Dave Land wrote:
I then
took a 1/4" drill bit and heated the back side till it was almost
red hot and shoved it through the jacket around where the other sensor
was located.
Holy CRAP!!! Office Depot has single-hole punches for $1.79 (you can
reach in through the center hole of the jacket and do each side separately),
but this definitely wins for Mr.-Joshua-in-Lethal-Weapon-style bad-ass-ness!
I don't think that anyone picked up on the solution
which I found that solved the problem (at least for
each floppy drive) permanently and no longer required
each floppy media to have additional index holes made
in the jacket.
Some floppy drives have two detection circuits. One
is for SS media when the standard index hole is offset to
the right by about 1 mm. The second is for DS media
for which the standard index hole is offset by about
10 mm to the right. One example of such a drive was
the DSD 880/30 which included an RX03 floppy drive.
I added a DPDT switch. The first position kept the
detection circuits identical to the factory standard.
The second position reversed the use of the index holes.
As a result, with the switch in the second position, the
floppy drive informed the software that a DS media
was present and both sides of the media could be used.
Note that even if SS media has been pre-formatted
(I presume that meant a Low Level Format which
neither DEC RX01 or DEC RX02 drives and
software were even able to perform), it was almost
certain that the second side of the media would not
have been LLF. At the time, I had a DSD 880/30
which included an RX03 8" floppy drive which is
able to support all the functions of a DEC RX02
floppy drive and controller. In addition, the DSD
RX03 floppy drive had a second head and the other
hardware support for DS media along with the
support to LLF all media using both SS and DS
index holes. Setting the DPDT switch to the second
position provided the ability to the user to LLF
(normally) SS floppy media as DS without the added
time required to punch a second pair of holes in the
jacket of each new SS floppy media.
Jerome Fine
