Toshiba FT-3808BK, Service Manual

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7. The voice of the caller can’t be heard (incoming call).
NG
OK OK
NG
OK
NG
OK
NG
OK
8. All keys of handset no function.
NG
OK
NG
OK
By using voltmeter, Check the
MCU-PWR of the handset. Check PIN15-28 of HU3 of handset
and surrounding circuit of U3.
By using voltmeter, Check PIN
15 of HU11 of handset.
Check the HU3 and around circuit
of HU3.
Check the battery and battery
contact.
Check the handset receiver
output.
Check the handset RX
sensitivity.
Check the base TX
power.
Check the base TX
modulation sensitivity.
Receiver of handset is
defective.
Check the RX IF circuit ( HU1 and surrounding circuit
of HU1 ) and RX AF circuit ( HU7 and surrounding
circuit of HU7 )
Check the handset RX RF
and mixer circuit ( around
HQ7)
Check the base TX circuit
using voltmeter.
Check the base TX AF
circuit ( around PIN 1-12
of BU6 ).
Receiver of handset is
defective.