25 Apr
2005
25 Apr
'05
1:53 p.m.
On Mon, 25 Apr 2005, jim stephens wrote:
The other thing you mentioned but didn't comment
on the condition of is
the grating and the optical sensor for said. are they clean? also, on
the drive's we had, of the western dynex and microdata variety, you
could physically feel the drive or the voice coil and feel it vibrating
when there was a servo problem, in most cases, or hear a difference
in the seeks as it failed.
It's pretty clean; I have not touched it. I can RTFM on cleaning
it, but the drive was very clean to begin with.
If there's a servo problem it's pretty subtle. I'm talking 10%
error rate (or whatever) not 100%. Mostly it reports in higher
cylinder numbers. This isn't a go/nogo problem -- I wish!
I will however stare at it and look for bulk odd behavior first.
I'm sure there's an error voltage off the servo I can look at, as
well as other nice closed-loop thingies. The documentation is
excellent, it has huge waveform diagrams and state diagrams (flow
charts).