Toshiba FD-4809, Service Manual

Page: 17 / 47

18
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 , 3 . 3 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 12 of
IC602 be fed? Check Q606 and its
peripheral circuit. NG
OK
TX output signal from the
handset is detected by the
liner detector, can the app.
30kHz pulse waveform be
fed?
Check handset RF unit.
NG
OK
Check whether there is the
1 kHz sine waveform at pin
22 of IC2 on the base unit. NG
OK
Check whether there is the
1 kHz sine waveform at pin
17 of IC2.
Check C7, R13, C10, R14.
NG
OK
Check whether there is the
1 kHz sine waveform at the
Q2 collector. Check Q2 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.
6. Voice cannot be transmitted to other party (outgoing call).