Commodore 1541 Maintenance Manual page 27

Troubleshooting-Part 1
The procedures apply to both the VIC-1541 and the 1541. The
locations of P4 and P8 have changed and the reference designators
have changed. Some gates of IC's have also changed. If you are
troubleshooting the 1541, be sure to cross reference the
designators and pin numbers given with those in the table in this
appendix. For example, Step 9 of Troubleshooting instructs the
user to short pin 10 of P6 to pin 10 of UF2E. After converting
the designators, the user would short pin 1 of P6 to pin 12 of
UBL
• FAILURE TO
CROSS
REFERENCE
DESIGNATORS
AND PIN NUMBERS MAY RESULT IN DAMAGE TO
YOUR 1541.
Troubleshooting-Part2
The procedures apply to both the VIC-1541 and the 1541 and may be
used by converting the reference designators and pin numbers.
Also note the changes described under Theory of Operation. Many
of the test points on the VIC-1541 are not available on the 1541
because they are inside UCl. Disregard these test points and any
reference to them.
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