Date   : Wed, 18 Dec 1985 16:30:51 GMT
From   : "J.S.Jonas" <jeffj%sfmin.uucp@BRL.ARPA>
Subject: disk errors [!PLEH]

[BDOS err on a: bad sector]

       I see that message way too often.  I am using NASHUA diskettes
purchased bulk from JDR, so the medium should be fine.
They start off error free, but then disaster strikes.
(well, I'm using ED until I get WS.  Could ED be bombing the disk?)
I think the sector CRC may be off.  Is there a program for CP/M
similar to FSDB that allows you to read a bad sector, edit it and
write it back with a new CRC?

       Should be fine is the correct phrase.  I added a DSDD drive,
and several diskettes have failed verification.  It is always
tracks >32 on side 1 (as opposed to side 0 which is used by SSDD drives).
I doubt it is the disk drive since it is only in the inner tracks
on one side (seek errors would be both sides, a bad head would be
all tracks.  Maybe the wire to the head?).
Cable problems would be intermittent.
I doubt it is the driver since it is side dependent.
Could it be the medium?  If anything I'd suspect the 0 side since
the bottom side seems to have a larger unpolished hub than side 1
(the upper side).  Any ideas?

       Thanks in advance.
                               Jeff 'this is frustrating' Skot
                               {ihnp4 | allegra | mcnc} attunix ! jeffj