Toshiba FT-8989, Service Manual

Page: 22 / 66

23
6. Voice cannot be transmitted to other party (outgoing call).
Can the base and handset be
connected? See 3. The base and handset
cannot be connected.
OK
NG
T h e 1 k H z , 9 . 0 m V s i n e
wave fo r m i s a p p l i e d t o
MC601 + side, can the 1 kHz
sine waveform from pin 24 of
IC601 be fed? Check Q604 and its
peripheral circuit. NG
Check whether there is the
1 kHz sine wavefor m at
pin 20 of IC601. Check IC601 and its
peripheral circuit. NG
OK
OK
Check whether there is the
1 kHz sine wavefor m at
C669. Check RT603 and its
peripheral circuit. NG
OK
TX output signal from the
handset is detected by the
liner detector, can the 1 kHz
sine waveform be fed?
Check handset RF unit.
NG
OK
Check whether there is the
1 kHz sine waveform at pin 9
of IC2 on the base unit. NG
OK
Check whether there is the
1 kHz sine waveform at pin 3
of IC3. Check RT2, Q2 and their
peripheral circuits. NG
OK
Check whether there is the
1 kHz sine wavefor m at
pin 18 of IC3. Check IC3 and its
peripheral circuit. NG
OK
Check whether there is the
1 kHz sine waveform at the
Q3 collector. Check Q3 and its peripheral
circuit. NG
OK
Check whether the 1 kHz sine
wavefor m from TEL-line
output is fed. Check T1, RL1 and their
peripheral circuits. NG
OK
Check MC601 of handset.
Check base RF unit and the
peripheral circuit of IC2.