Digital Equipment DECwriter 500i Service Manual page 7

5. DIAGNOSTICS AND TESTS
5.1 AUTODIAGNOSTICS AT POWER-ON ................................................ 5-1
5.2 PRINT TEST WITH BLACK PRINT HEAD.......................................... 5-1
5.3 PRINT TEST WITH COLOR PRINT HEAD.......................................... 5-3
5.4 "DATA SCOPE" PRINTOUT (HEX DUMP) ....................................... 5-4
Enabling the Data Scope printout:.......................................................... 5-4
Disabling the Data Scope printout:........................................................ 5-4
5.5 DIAGNOSIS GUIDELINES .................................................................. 5-5
6. FAULT CONDITIONS AND MEANING
OPERATIONAL STATUS ........................................................................... 6-1
Fault Conditions and Indications............................................................ 6-2
Normal Conditions and Indications ........................................................ 6-3
7 MECHANICAL ADJUSTMENTS
7.1 PRINT HEAD AND THE WRITING SURFACE GAP.......................... 7-1
Procedure:.............................................................................................. 7-1
7.2 ADJUSTING THE TENSION OF THE PAPER FEED MOTOR BELT.. 7-2
Procedure:.............................................................................................. 7-2
7.3 BI-DIRECTIONAL PRINT ALIGNMENT ADJUSTMENT ................... 7-3
8. ELECTRICAL INTERCONNECTIONS
8.1 MAIN BOARD MAIN COMPONENTS ................................................. 8-1
8.2 POWER SUPPLY BOARD..................................................................... 8-2
8.3 POWER SUPPLY CIRCUIT ON MAIN BOARD................................... 8-3
8.4 CONNECTOR SIGNALS ....................................................................... 8-4
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