IBM 6400-I15 Maintenance Manual - Page 135

Operator Print Tests A set of print tests is included in the configuration menu structure for use as diagnostic tools. These are called the "Operator Print Tests" because they are available to the user. You can use these print tests to check the print quality and basic operation of the printer. The Operator Print Tests are summarized below. NOTE: Under the description of some tests is a list of items that may need to be adjusted or replaced if the test produces a bad print pattern. The items are listed in the order you should check them: simplest items first, complex items last. ♦ Printer Demonstration Prints a sample page showing every print mode, font, and pitch available in the printer. ♦ Print Error Log Prints the contents of the error log. The error log automatically records certain unit check conditions in a buffer in NVRAM that stores up to 50 messages. The most recent message is stored at the top of the list, the oldest message at the bottom of the list. If more than 50 messages occur before the log is cleared, the oldest messages are deleted, so that the log never contains more than 50 messages. ♦ Ripple Print A "sliding" alphanumeric pattern useful for identifying missing or malformed characters, improper vertical alignment, or vertical compression. Hammer bank cover Hammer spring Shuttle frame assembly ♦ All E's A pattern of all uppercase letter E's useful for identifying missing characters, misplaced dots, smeared characters, improper phasing, or light/dark character variations. Ribbon Splined shaft skew adjustment Hammer bank cover MPU sensor Hammer springs Hammer coils (shuttle frame assembly) ♦ All H's A pattern of all uppercase letter H's useful for detecting missing characters or dots, smeared characters, or improper phasing. Troubleshooting 135