Apple Mac 5260/100 - Manual (Page 196)

5260 and 5280 Adjustments Geometry - 13
Focus
1 Run Display Service
Utility to display the
Focus test pattern.
2 Using a flat-head plastic
adjustment tool, adjust
the focus control on the
flyback transformer
until the Focus test
pattern reaches the best
center-of-screen
performance.
Focus Control
Flyback
Transformer
Run
Display Service
Utility
Focus
Test Pattern