Nokia 920C Service Manual page 32

5 Troubleshooting
5-2-7 Poor Focus
Adjust focus VR.
Improved focus?
No
Check focus leads from FBT
to CRT Socket.
Check the CRT Socket.
Is dynamic focus circuit right?
Yes
Replace the CRT and verify focus.
5-2-8 Purity Failure
Degaussing
Purity is right?
No
Degaussing circuit is right?
Yes
Replace CRT and verify purity.
5-18
Yes
Aging monitor and check for focus
change.
No
Refer to 5-1-15 Dynamic
Focus Failure.
Yes
Done
No
Refer to 5-1-20 Degaussing Failure.
720C/920C