I want to buy an oscilloscope exclusively to head the pcbs of the hard-disk.
I suggested some model to not spend so much?
Thanks

Check ebay for Lecroy DDA.
Expect between 2000 to 7000 $ for a second hand model depending on the condition it has.
And you will need a differential probe which will cost the same amount of money.

Dobre

_________________
Murphy was an optimist

Datarecovery in Belgium, Holland, France and Germany
Datarecoverytools http://www.drtools.eu

I use Agilent and LeCroy, the prices are comparable. The diff probe thing is sad but true. You can save something by searching for surplus or ex-lab, but be sure it is working and calibrated !