19 Jun
1998
19 Jun
'98
3:30 a.m.
<"But 3.5" diskette drives are too difficult to modify. We've had good
<read and write results by passing the index signal through a 1-shot
<carefully adjusted to trigger slightly ahead of the actual index
<position. But this is a very touchy arrangement, though it does work.
<
<I know that I have experienced the problem of the first paragraph on more
<than the C10 disks.
< - don
Some formats produced with 1771 or 179x can be nasty. The fix is to delay
the index using two oneshots one set long (95% or a rotation) and the
second long enough to provide a recognizable pulse. This trick can permit
you to "move" the index sensor as needed electronically.
Allison