I've got a Hitachi 250GB that doesn't spin up. It doesn't spin up with a PCB from a good drive, same model. The good drive spin up with the PCB of my drive. What might be the reason for such a behaviour? Any suggestion how to solve the problem?

Hi,

maybe spindle is stuck, or the heads are not parked and they are stuck onto the platters preventing it from rotating.
Or the windings might be broken.

regards,
pepe

The spindle is OK. It spins up normally if I use a PCB from an older IBM drive.

then it might be the preamp that is defective.
check it by a multimeter and compare to a good drive.

pepe

Hi Pepe,
This Is What You Always Say ,Can You Tell Us The Method As There Are No Many Connections To The Preamp .Might Be Some Datasheets Could Help

_________________
Regards
Amarbir S Dhillon , Chandigarh Data Recovery Labs [India]
Logical,Semi Physical And Physical Data Recovery
Website-> http://www.chandigarhdatarecovery.com

I doubt that's what you had from the beginning.
Tell us more about the initial problem of the drive. That could help.

Amarbir
Hi,

As I wrote it is possible to check the preamp against short circuit on the power lines, check other data/controlling lines by COMPARING to a working drive of the same family. I don't have datasheets, but it would not tell us how to do comparing either.
I usually give hints to forum members, I cannot spend my time just sitting and telling step by step solutions. It would not be good for others, since their brain would be gone soon
I learned many things by spending many time by experiencing, and it is the same now - I have to learn a lot mostly by myself, a forum is not a place I would like to publish all these things, but I am ready to give the first hint where I would start with a case.
If U want lessons, well I am afraid this is not a quite good place for it...

regards,
pepe

Cleared ,
I Have Got That Little Brain As You Mentioned ,Just a Hint Is Enough .Well Analyzing a Signal With a Scope or Signals Collectively Might Be e Good Idea .Also If Its Short It Could Be That The Voltage In The Preamp Area on The PCB [ Output Signals ] Voltages Will Drop [Due To Shorting ]

PS :Right BOSS IS The Brain On The Right Track ,With Friends Like HDDGURU And You I Think So

_________________
Regards
Amarbir S Dhillon , Chandigarh Data Recovery Labs [India]
Logical,Semi Physical And Physical Data Recovery
Website-> http://www.chandigarhdatarecovery.com

Guy's you will find that a 90G spec sheet is impossible to find. Just compare voltages from your working PCB to your non working and I'd check current at the spindle connections (across the phases) and you will find your answer.

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I think ST is a sub company of Lucas