Voice Cannot Be Transmitted To Other Party (Outgoing Call) - Toshiba FT-7800A Service Manual

6. Voice cannot be transmitted to other party (outgoing call).

Can the base and handset
be connected?
OK
Apply the 1 kHz, 9 mV sine
waveform to MC601 +
side, can the 1 kHz sine
waveform from pin 12 of
IC601 be fed?
OK
Check whether there is the
1 kHz sine waveform at
pin 8 of IC601.
OK
TX output signal from the
handset is detected by the
liner detector, can the 1 kHz
sine waveform be fed?
OK
Check whether there is the
1 kHz sine waveform at
pin 28 of IC1 on the base
unit.
OK
Check whether there is the
1 kHz sine waveform at
pin 29 of IC1.
OK
Check whether there is the
1 kHz sine waveform at
pin 50 of IC1.
OK
Check whether there is the
1 kHz sine waveform at the
Q3 collector.
OK
Check whether the 1 kHz
sine waveform from
TEL-line output is fed.
OK
Check MC601 of handset.
NG
See 3. The base and
handset cannot be
connected.
NG
Check R621, R622, R691,
C636, C637, C712, C713
and their peripheral circuit.
NG
Check IC601 and its
peripheral circuit.
NG
Check handset RF unit and
its peripheral circuit of
RT603.
NG
Check base RF unit and the
peripheral circuit of IC1.
NG
Check RT2 and its
peripheral circuits.
NG
Check IC1 and its
peripheral circuit.
NG
Check Q3 and its peripheral
circuits.
NG
Check T1, RL1 and their
peripheral circuits.
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