WD40NMZW spyglass questions

[skeeter]

I have a spyglass drive that I am trying to learn from
Customer is happy with what was retreived, so I can experiment on this drive

I was able to image most LBAs - 1.8million errors out of 7.8billion
I can get SA access, but have not altered anything yet

the remaining errors are in chunks of varying size. they all return UNC errors.
for example, BAD LBAs:
2000 - 243343
250096 - 376383
741952 - 742151

has anyone seen this before ?

[pepe]

i would bet they are on one head, however 1.8M is too few for a whole surface. Except if it had very few data. How much data does it have?

pepe

[skeeter]

it is about 3/4 full (3tb)
most are on head 0, but some on head 8 & 9

my gut tells me it is bad media, but I just want to get anyone else's opinion

here is a detail of some of the larger unreadable areas:

startLBA endLBA size
2000 243343 241343
250096 376383 126287
741952 742151 199
231651416 231657687 6271
236692176 236699463 7287
237167576 237173719 6143
1053300016 1053310039 10023
1053310424 1053314215 3791
1405577304 1405583359 6055
1405703526 1405709007 5481
2065955184 2066102511 147327
2066242400 2066332494 90094
2066439672 2066447063 7391
2066523008 2066775815 252807
2238266152 2238303239 37087
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