Toshiba FD-4809, Service Manual

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17
4. Cannot make a phone call (pulse).
Can the base and handset
be connected? See 3. The base and handset
cannot be connected.
While in TALK MODE, press
dial key of the handset.
Check whether square
waveform from pin 46 of IC4
is fed. Check IC4 and its peripheral
circuit.
Check Q9, RL1 and their
peripheral circuits.
NG
OK
OK
5. Cannot make a phone call (tone).
Can the base and handset be
connected? See 3. The base and handset
be cannot be connected.
OK
NG
While in TALK MODE, press
dial key of the handset.
Can tone waveform from Pin
17 of IC2 is fed?
OK
NG
Can tone signal be heard
from the handset speaker? Check Q2 and its peripheral
circuit. NG
OK
Check the base TEL-line
circuit and RELAY control
circuit.
NG
Check IC2 and its peripheral
circuit.