HP C7769B Service Manual - Page 103

Service Calibrations WARNING Printhead Alignment (includes PPS Calibration) The purpose of the Printhead Alignment is to correct the alignment between the Printheads in order to prevent color misalignment and print quality defects like banding. Normally the Printhead Alignment is performed automatically whenever the printheads are replaced. The Printhead Alignment also contains the Pen to Paper Spacing (PPS) Calibration which is used to solve Vertical Line Straightness (VLS) problems. During normal operation, the PPS calibration will not be performed automatically whenever the Printheads are replaced, even though the Printhead Alignment will be performed automatically. There are two options available when performing the Printhead Alignment: n Standard - Use this when only the Printheads need to be aligned. This Alignment normally takes about 4½ minutes to be completed and requires media of at least A4/Letter-size (loaded in landscape). n Special - Use this when VLS problems have been detected when printing line drawings on wide media (36" to 42") in Fast Mode. Using this option the Printer will perform both the regular Printhead Alignment and the PPS Calibration. This Alignment normally takes about 11 minutes and requires media of at least A3/B-size (loaded in landscape). Perform the Printhead Alignment as follows: Make sure you use HP Bright White InkJet Paper (Bond), HP Coated Paper, HP Heavy Coated Paper, HP High-Gloss Paper, HP Satin Paper or Plain Paper. If you try to use any other type of Paper the Printer will not allow you to perform the Alignment. 1 In the Service Calibrations submenu, scroll to "Align printheads" and press Enter. Service calibrations Align printheads Color calibration Advance calibration Factory advance cal. Menu Back Enter 2 The following message will appear asking you if you want to perform the Standard alignment or the Special alignment. Select HP DesignJets 500 and 800 Series Printers Service Manual 5-5