RL02K Pack Reliability/Characteristics
pete at dunnington.plus.com
Wed Apr 1 05:01:39 CDT 2015
On 01/04/2015 04:58, Johnny Billquist wrote:
> On 2015-04-01 05:26, Christopher Parish wrote:
>> Thanks for your help everyone. I finally figured out what was
>> happening. Something is wrong with my (everyone's?) drives.
>> In the process, I have confirmed that sometimes the drive does
>> mis-seek when making larger jumps across the pack. A single follow up
>> seek is almost always enough.
> This sounds strange. Are you sure you are not just fiddling with the
> head here? A head switch will taste like a seek, but it might actually
> not move you as you would expect...
It does sound strange. As I mentioned a couple of days ago, I've been
ministering to an RL02 that occasionally had problems on the outer
tracks (possibly elsewhere but I never noticed that). Copying packs and
almost all seek/read/write worked fine but a very few operations didn't.
All the voltage, alignment and timing tests in the technical manual
checked out except for jitter running the oscillating seek tests (access
time checks) - especially for longer seeks. To cut a long story short,
there was a fault in the drive's DLM. Replacing it removed the jitter
and the drive now behaves perfectly.
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