Aligning The Heads On A 9 Track Tape Drive
| Field | Computing |
| Went Obsolete | 1990s |
| Made Obsolete By | RAID Hard Disks Arrays |
| Knowledge Assumed | Dual trace Oscilloscope |
| When useful | 1970s and 1980s |
Obtain a master head alignment tape. Treat this with care. Mount the MHA tape and start the drive reading forward. Pick up the output of the two centre tracks. I think that was 4 and 5. Adjust the forward skew POT of one track until the two plots on the oscilloscope match.
Leave track 4 in place as a reference and change the oscilloscope to either track 6 or 3. Repeat alignment via POT. Repeat until all tracks have been aligned. Repeat entire process as a re-check to insure nothing has drifted. Repeat process for reverse read. This might not be important to some systems as most tape were only read in the forward direction.
Stop tape reading foreard. Rewind as slow speed. Fast rewinds can ruin a MHA tape.