TROUBLESHOOTING HINTS
1. No Character
No Character
Are the
Change the Contrast &
Contrast &No
Brightness control to
Brightness Controls
maximum
maximum
Yes
Is wholeNo
Refer to
screen bright?No Raster
No Raster
Yes
Is CRT
Yes
Cathode (Rk, Gk, Bk)Check the peripheral circuit
signal levelof CRT Board
normal?Rk, Gk, Bk
NoAbout 40Vpp
Is the
output signal of the
YesCheck the video output
(pin 16,18,20) pre-amp(IC802, TDA9536) and
(IC801, TDA9210)their ambient circuit
normal?
No
Is 6.3Vdc lineNoTrouble in 6.3Vdc line
normal?of the Main PWB
Yes
Is blankingNoCheck the blanking pulse
pulse (pin 20 of IC801)
circuit
normal?
Yes
Is input signalNo
Check the signal cable
normal?
Yes
Trouble in IC801 and
its ambient circuit
17 |