Restore database from old RMAN backup

1. As usual, you use catalog command to recatalog your backup pieces.
catalog backuppiece '/db/backup/MYDB/old_backup/your_piece_1_1';
2. Startup nomount and restore controlfile.
RMAN>restore controlfile;
3. Alter database mount and restore database
RMAN>alter database mount;
RMAN>restore database;
4. Try recover database;
It will give you the required archivelogs but you don't need them. You are just trying to restore from the old backup as it was. So check you max last archivelog in thi sbackup:
select max(sequence#) from v$log_history;
1425
Now do this:
Recover database until logseq=1426;
5. You are done.
Run:
Alter database open
6. And don't forget to create you tempfiles. RMAN backup does not have them!