Ntsc Channel No Picture; Atsc Channel No Picture - Insignia NS-LCD32 Service Manual

(6) NTSC channel no picture

Check if CB154 outputs
signals?
Yes
Check
periphery circuit

(7) ATSC channel no picture

Check if the crystal is
normal? If output signal?
Yes
Check socket N100 and the
periphery.
Note :
The I2C bus line control of TUNER is switch through the bus line of N228, so after checking the power
supply and peripheral circuit of TUNER226, it is still no picture in NTSC and ATSC channel, please
check N228 emphatically.
Check if pin4 of TUN1 output
signals?
Yes
N100 and its
Check if pin20/21 of TUN1
output signals?
Yes
No
No
Check TUN1 power supply and
the peripheral circuit.
No
Check TUN1 power supply and
the peripheral circuit.
Check the crystal
periphery circuit.
24
and