TITLE
Duodisk General Troubleshooting 

Article ID: 1394
Created: 10/24/85
Modified: 1/30/92
 

--------------------------------------------------------------------------------
TOPIC 


--------------------------------------------------------------------------------
DISCUSSION 


DESCRIPTION:
By following this procedure you can isolate a malfunction on the Duodisk and
determine whether or not it is functional.

YOU WILL NEED:
1. "Known good" Apple IIe computer
2. Two DOS formatted 5 1/4 disks (one write protected the other not)
3. "Known good" Duodisk controller PCB - IN SLOT 6
4. 2 copies of DAP (Drive Acceptance Program) (APN 077-8101) - it is copyable
5. DDD (Digital Diagnostic Disk) (APN 689-8024)
6. Level I Tech Procedures

BEFORE YOU START:
1. If replacement or adjustment procedures are needed, refer to the Tech
Procedures
2. If a replaced module/part doesn't fix a problem, reinstall the original
module/part.
3. If the analog card proves to be problem, search on "HTS and Duodisk and
Analog" for the analog card troubleshooting procedure.
4. After repair, check drive with "other" DAP disk (original may be damaged).

INSTRUCTIONS:
1. Connect the problem Duodisk to the controller in the Apple IIe.
2. Boot the DAP disk in LEFT drive.

a. First screen shows 2 drives and 2 arrow keys.

b. You run the program with the 2 arrow keys.

c. If drive booted OK, go to step 3; if not, check for problems below.

PROB: Won't boot. Drive comes on but I/O errors occur
FIX: Recheck for the problem after each of the following steps
(1) Try other DAP disk.
(2) Try reading a file from the other drive on the Duodisk. If it
fails, replace analag card.
(3) Perform Dspeed adjustment in Tech Procedures (you'll need to use a
known good drive in addition to the problem drive to make this
adjustment). If the problem drive won't adjust, replace analog card
(4) Examine the head. If dirty, clean it with solution of 80% denatured
alcohol and 20 % distilled water (for more info search on Disk Drive
Preventive Maintenance); if the head is scored replace the mechanical
assembly containing the head.
(5) Replace interface cable
(6) Replace disk mechanical on the problem drive
(7) Replace analog card

PROB: Won't boot. Drive doesn't come on.
FIX: Recheck for problem after each of the following steps
(1) Boot from other drive on Duodisk. If it fails, replace analog card.
(2) Replace interface cable
(3) Replace disk mechanical
(4) Replace analog card

PROB: Drive makes unacceptable noise
FIX: Replace disk mechanical


3. Press "LEFT" arrow to select "LEFT" drive for test.

4. Screen asks you to install WRITE-PROTECTED blank disk into drive. After
you do, press the RIGHT arrow to continue running the test...drive whirs.
Read IMPORTANT below.


IMPORTANT: If a failure occurs during the following steps, the drive under
test will be crossed out and the number(s) above the crossed out drive will
indicate which test(s) failed. If this happens, go to the end of this
procedure find the Test #(s) that failed and perform the appropriate repair
action.


5. The changing arrows on the screen tell you to remove the WRITE-PROTECTed
disk and install NON-WRITE-PROTECTED blank disk into drive. After you do,
press RIGHT arrow to continue running the test...drive whirs test numbers
change as tests are performed.

6. After a minute or so and while drive is still whirring, screen asks you to
install DDD disk. After you do, PRESS the RIGHT ARROW to continue
tests...drive continues to whir, DDD disk change screen leaves, etc.

7. The drive stops whirring and the screen asks you to remove the DDD disk,
this is the end of the test and indicates that the LEFT drive is OK so
press the LEFT arrow once to go back to the first screen, then press RIGHT
arrow to select RIGHT drive for test and go back to step 4.


If a failure ocurred in the procedure above, find the Test #(s) that failed
and perform the appropriate repair action.

TEST# - REPAIR ACTION

1 Make sure test was done using proper disks (i.e., DOS 3.3 formatted,
blank, write protected/non-write protected).
Replace disk mechanical
Replace analog card
Send to Apple

2 Adjust D-Speed
Replace analog card
Replace disk mechanical
Send to Apple

3 Replace analog card
Replace disk mechanical
Send to Apple

4 Rerun test (test 4 failure can indicate bad DDD disk)
Replace disk mechanical
Send to Apple

5 Replace disk mechanical
Send to Apple

6 or 7 Replace disk mechanical
Send to Apple