PURPOSE: To adjust the picture quality in compliance with the applicable one of many tube types by providing a means to add another function to an automatic picture quality adjusting device, and furnishing a higher order computer separate from the computer included in this automatic adjusting device for processing the mentioned means.
CONSTITUTION: An automatic picture quality adjusting device 12 adjusts the picture quality using a computer 21 automatically when a deflection yoke is fixed to a color display tube. A total processing analyzer part 35 makes statistical analysis of the service situation of the auto. adjusting device 12, while a database part 34 stores the data about the adjusting ability and the results from adjusting by this adjusting device 12. An adjusting law deciding part 33 converts the adjusting law, when the device 12 makes adjustment, according to the type of the applicable color display tube and a higher order computer 11 correcting the adjusting law according to the adjusting ability processes the means 33-35. Thereby picture quality adjustment can be made in compliance with the type among many provided.