Activate DB on different server if mounted

Hi,

I'm trying to write a script that will check to see if a DB is mounted on a specific server, and if it is mounted, activate it on a different server.  Below is what I have so far, but not working:

$dd1=Get-MailboxDatabaseCopyStatus -Server xxxx
if ($db1[0].Status -eq "mounted")
{
      Move-ActiveMailboxDatabase -ActivateOnServer yyyy -MountDialOverride 'none' -Confirm:$False
}
else
{
exit
}

The error that I am getting is :

Cannot index into a null array.
At C:\DBSwitch.ps1:2 char:10
+ if ($db1[ <<<< 0].Status -eq "mounted")
    + CategoryInfo          : InvalidOperation: (0:Int32) [], RuntimeException
    + FullyQualifiedErrorId : NullArray


I'm thinking that it doesn't like my variable declaration.

I can do it another way, but that would require me to "manually" enter each DB name.  This is not what I am looking for as I need to make this a scheduled task.