unreadable output file in powershell

If you redirect a not-completly-string output (like a spfile) to a file in powershell, you may not see the same in the file as in the output

• without redirection
  
PS C:\> Select-String "compatible" .\spfileDB01.ora
spfileDB01.ora:13:*.compatible='11.2.0.4.0'

• with redirection
  
PS> Select-String "compatible" .\spfileDB01.ora > compatible.txt
PS> vim -b .\compatible.txt
ÿþ^M^@
^@s^@p^@f^@i^@l^@e^@D^@B^@0^@0^@1^@.^@o^@r^@a^@:^@1^@3^@:^@*^@.^@c^@o^@m^@p^@a^@t^@i^@b^@l^@e^@=^@'^@1^@1^@.^@2^@.^@0^@.^@4^@.^@0^@'^@^M^@
^@

• With redirection and conversion to ascii
  
  PS> Select-String "compatible" .\spfileDB01.ora |
  Out-File -Encoding ASCII .\compatible.txt

  PS> vim .\compatible.txt

  spfileDB01.ora:13:*.compatible='11.2.0.4.0'


With Out-File (instead of >), you can specify the encoding, which does the trick