HP used a cartridge system that you got new jets with each cartridge.
When dots go missing either the contacts to the cartridge have failed (try cleaning with alcohol soaked q-tip) or the electronics has failed (repair shop time.)
Bob
I have an HP1150c, now nearly 10 years old but still worth having. It no longer prints properly and looks as if some of the ink jets have dried and clogged. Even a new cartrige does not work.
Does anyone have a suggestion for how to get this up and running again?

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