Hi,
I was googling around and I know that its a problematic drive, the Seagate ST3500820AS. Mine comes from LACIE external But this is rare issue:

When I power it on, it repeatedly buzzes silently in about two second intervals, the spindle motor makes this buzzing as the spindle controller tried to spin it up. The PCB is fine, I checked the power diodes, all are fine, and SMOOTH controller looks fine since I see that voltages are jumping on the 3-pin connector to spindle motor.

The drive has not been dropped heavily or abused in any way. It just stopped working. What I can think of is that heads are not parked and preventing the spindle from spinning the drive. Or is this seized motor? How do I find this out?

If I go out in fresh winter day far away from any dust sources and quickly open it only to check the position of heads - is it going to create any damage to the surfaces?
I have red about some older HDDs that it was possible to un-stuck the heads from surface by rapidly rotating the HDD itself in both directions making spindle to move by force of inertia, but on this one it does not work.

Please tell me what to do with this drive. Thanks!

spindle seizure, send it to a pro

dont open it, and if this data is something to care about - do send it to a pro. even if the heads just got stuck to the platters - there is a very small chance you will get it fixed by yourself.

It's a very simple case for a PRO, with a reasonable price.

but you may crash the heads and make scratches on the platters if you do it yourself. And the price will be double or higher.

???

Not simple

You have to rotate the spindle motor carefully and release the heads then move them to the head's park, power on then everything will be ok.

I think it's not a special case for a pro, Andrew ?

Take it to a pro.

If you are a chemist, it is simple to make Nitro Glycerine, if you are not a chemist and you get it wrong you end up with no house. This wont matter as it will probably kill you.

What is simple to one who knows can be the disaster for those that dont.

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I dont need a gun, I've got a Donk
http://www.youtube.com/watch?v=CwpZFsVyues

But what will PRO do to that HDD? If the spindle motor has been seized then you need to swap a motor, this, indeed, can be done only in the lab with special tools (cylinder to remove all platters ar once etc..) but if thats the case of heads left on the surface then what PRO will do is get them off the surface and move to parking position. Now I dont know how many heads / platters this drive has, I asume two heads, one platter, so it should not be too hard to slightly pull the arm holding the head away from the surface to release it and then slowly let it land back to the surface.
Or even insert appropriate spacer between the arms that keeps the heads slightly off the surface and move them away to parking position.
But first I have to check if the heads are on the surface or not.

A pro will have a special tool to remove heads from platters. Different pros have different tools.

If non of those advices are good for you, then you might as well hit your drive hard enough to release a spindle, it will get you same results as if you do every thing described above. Result will be - data is unrecoverable.

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www.datarecoveryne.com

2 platters, 4 heads.
well, if heads are stuck to the surface, and the spindle is fine, the case is relatively simple, but can go wrong if not done properly.
However I thing the problem is not that heads are stuck, but that the spindle is seized, which is a far more complicated thing.
without experience and tools it is quite like Donk mentioned.

pepe

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Adatmentés - Data recovery