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Diagnostic Tools

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Check Drive will attempt to determine whether your drive is functioning normally. Check Drive requires a formatted disk appropriate for your drive to complete testing. When you select Check Drive, the Applesauce client will test whether your drive is connected to the Applesauce device, is consuming appropriate power, reads, writes, has normal head tracking, whether write protect is working, and (for Apple II drives) if a sync sensor is installed.

  • If your drive has abnormal power consumption (red numbers), there may be a hardware issue with the drive. Mechanical issues such as drive rails in need of lubrication can cause elevated power consumption. Careful application of mechanical silicone oil to the drive rail may improve head motion and reduce power consumption. Other lubricants such as WD-40 are not recommended and may be detrimental to the drive in the long run. Yellow numbers are only slightly abnormal, and may still allow for the drive passing the other Check Drive tests.
  • If your drive fails to read your test disk (a red X appears above Reading instead of a green check), Diagnostic Tools will not continue to test disk writing or tracking. Refer to the Troubleshooting section.
  • If your disk is write protected, your drive will fail the Write Protect sensor check (red X) and Check Drive will not be able to test your drive's ability to write.
  • Check Drive will overwrite a track on your formatted disk (track $22 on Apple II drives).

   Abnormal power consumption is demonstrated in the screen above, which suggests an issue with the drive motor, causing abnormal spindle speed. 

Speed Test

Speed Test checks that the spindle speed is correct. Expected values:

Apple 5.25“ double density 300 rpm/200 ms rotation time
PC 5.25” low/double density 300 rpm/200 ms rotation time
PC 5.25“ high density 360 rpm

Speed Test will run for a while to allow you to adjust the speed of your drive. Speed test will overwrite a track of your formatted disk if you are using a PC drive or if you are using an Apple II drive without a sync sensor installed. If you have a sync sensor installed, no disk is necessary for the Speed Test. Sometimes PC drives need different jumper settings to let the host control the drive speed, which can result in Speed Test failure if not set correctly.

== Troubleshooting ==

  • Always power down your drive before you disassemble or attempt to repair it by unplugging the Applesauce unit from USB power.
  • Verify that you have a formatted floppy of the correct density and correct type. If the floppy is not formatted, formatted for the wrong drive, or formatted at the wrong density, Applesauce can not verify that the drive is reading the disk correctly. If you do not have the correct kind of formatted disk, you can try setting the drive profile manually and then using the ''Disk Writer'' to create a formatted disk. Note also that Drive Profiler will overwrite tracks of your disk while performing initial testing, which may interfere with Check Drive read test, unless you use a reformat the disk or use a different formatted disk for testing.
  • The most common cause of a read error is a dirty head. Try running the Clean Head routine in Fast Imager with a cleaning disk, or manually clean the head after disassembling the drive. If you are using a 3.5” drive, never attempt to clean the heads manually. Only use a cleaning disk to clean the heads of a 3.5“ drive.
  • If you are using a Disk ][ drive, the next most common cause of a read error is failure of the 74125 IC (same as 74LS125) on the Disk Analog Card inside the disk drive. The 74125 IC may also result in abnormal power consumption in a Disk ][. Occasionally 74125 IC failure results in the drive uncontrollably overwriting Track $00, which destroys disks. The next most common point of failure is the MC3470 IC, which is also on the Disk Analog Card. If can be useful to test these chips by substitution with replacement or known good ICs. The ULN2003 IC, which controls the stepper motor, may also occasionally fail, resulting in absent or abnormal head movement.



  • Explain what all of the measurements mean.
  • Explain what all of the tests mean.
  • Better troubleshooting.
  • Spindle Test: other drive types