Receiver Trouble - LG L1100 Service Manual

4.8 Receiver Trouble

Block Diagram
Calypso
(U102)
SPK_EN
IOTA
(U101)
Melody Generation
• U201(YMU762,MIDI) is controlled by DBB.
• U201 generates 40poly MIDI sound and it is delivered to the speaker
• When SPK_EN is 'H', EAR_SPK from U203 is delivered to the speaker
through U201
Signals to the receiver
• RCV_P,RCV_N From ABB
• EAR_N, EAR_P are delivered to Receiver, when SPK_EN is 'L'
Check Points
• Audio signals from ABB
• Audio signals to the receiver
• Audio signal path
• Check the sound level to the speaker.
• Soldering of connectors, speaker and receiver
• Speaker
• Receiver
Control
Analog SW
(U203)
EAR_SPK
RCV_P/
RCV_N
SPKP/
YMU762
SPKN
(U201)
EAR_P/
RC filter
EAR_N
-57-
CN701
(CN3)
SPEAKER
RECEIVER