Norcent LT2722, Service Manual

Page: 26 / 77

Norcent LT2722
25
Audio Control Block
No Sound
Check CN604, CN609
and L613, L614, L616,
L617
Replace speaker
Check U603, U604 output
relative circuit and power
supply 24V
Check CN602 Pin3-4 and
Pin1-2 are short when no
ear-phone plug
Check earphone board
Check U200/U105 output
relative circuit
Check TUNER
Pin11 to U105
relative circuit
Check U600, U601 output
to U105 relative circuit
Check U600, U601
input signals
OK
OK
NG
NG
NG
NG NG
NG