Mis-Alignment for sure.
Only way to align these, is on a test bench. You must have a test disk, or a disk with physically/mentally known magnetic patterns, and you must force the drive spindle motor to ON.
Take an oscilloscope and hook to the head assembly.
Then move the head on track 0, and turn the stepper motor itself physically until the scope shots are at thier maximum peak. The drive is aligned.
Stepper motors move so many degrees per step. CANNOT move anywhere in between. If the head looses "alignment" it will land "in-between" during steps. you must physically turn the motor while watching the heads from an oscilloscope using a known good test disk.
thats track alignment.
Disk-to-head tension alignment i havent figured out yet, this will cause weak pickup as well as track mis-alignment. Think of cassette tapes here. same principals apply.
The reason this cause disk rejection errors, is because when the drive goes to record, it writes the data on the tracks which are now "misaligned" from the REAL track positions. So it doesnt fully "erase" what was left in the real track positions, if its less than 90 degrees away from the adjacent "real" track.
So what you do is get data "clobbered" together. the drive reads the new data, and the old data at the same time, causing errors.
If its fully mis-aligned, that means your new tracks are equidistant between the leading and trailing track records, so the head cannot "see" the adjacent recorded data. The floppy will write and read just fine. however, will not read in ANYTHING else unless the drive has the same alignment. (i have done this before. )
Only way to align these, is on a test bench. You must have a test disk, or a disk with physically/mentally known magnetic patterns, and you must force the drive spindle motor to ON.
Take an oscilloscope and hook to the head assembly.
Then move the head on track 0, and turn the stepper motor itself physically until the scope shots are at thier maximum peak. The drive is aligned.
Stepper motors move so many degrees per step. CANNOT move anywhere in between. If the head looses "alignment" it will land "in-between" during steps. you must physically turn the motor while watching the heads from an oscilloscope using a known good test disk.
thats track alignment.
Disk-to-head tension alignment i havent figured out yet, this will cause weak pickup as well as track mis-alignment. Think of cassette tapes here. same principals apply.
The reason this cause disk rejection errors, is because when the drive goes to record, it writes the data on the tracks which are now "misaligned" from the REAL track positions. So it doesnt fully "erase" what was left in the real track positions, if its less than 90 degrees away from the adjacent "real" track.
So what you do is get data "clobbered" together. the drive reads the new data, and the old data at the same time, causing errors.
If its fully mis-aligned, that means your new tracks are equidistant between the leading and trailing track records, so the head cannot "see" the adjacent recorded data. The floppy will write and read just fine. however, will not read in ANYTHING else unless the drive has the same alignment. (i have done this before. )