Toshiba FD-9839 Service Manual page 19

4. Cannot make a phone call (pulse).
Can the base and handset
be connected?
OK
While in TALK MODE, press
dial key of the handset.
C h e c k w h e t h e r s q u a r e
waveform from pin 46 of IC8
is fed.
OK
Check R83, D11, Q11, RL1
and the peripheral circuit.
5. Cannot make a phone call (tone).
Can the base and handset be
connected?
OK
While in TALK MODE, press
dial key of the handset.
Can tone waveform from Pin
23 of IC2 is fed?
OK
Can tone signal be heard
from the handset speaker?
OK
Check the base TEL-line
circuit and RELAY control
circuit.
NG
See 3. The base and handset
cannot be connected.
NG
Check IC8 and its peripheral
circuit.
NG See 3. The base and handset
be cannot be connected.
NG Check IC2 and its peripheral
circuit.
NG Check IC3, Q3, Q4 and the
peripheral circuit.
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