Toshiba FT-8939, Service Manual

Page: 22 / 62

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
MC401 + side, can the 1 kHz
sine waveform from pin 24 of
IC403 be fed? Check Q404 and its
peripheral circuit. NG
Check whether there is the
1 kHz sine wavefor m at
pin 20 of IC403. Check IC403 and its
peripheral circuit. NG
OK
OK
Check whether there is the
1 kHz sine wavefor m at
pin 23 of IC403. Check RT403 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 IC3 on the base unit. Check IC3, Q1 and their
peripheral circuit. NG
OK
Check whether there is the
1 kHz sine waveform at pin 3
of IC1. Check RT2, Q2 and their
peripheral circuits. NG
OK
Check whether there is the
1 kHz sine wavefor m at
pin 6 of IC1. Check IC1 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 MC401 of handset.
Check base RF unit.
NG
OK