Toshiba FT-7007LBR, Service Manual

Page: 18 / 43

19
7. The voice of the caller cannot be heard (incoming call).
Can the base and handset be
connected? See 3. The base and handset
be cannot be connected.
OK
NG
The 1kHz 97.5mV sine
waveform is applied to
TEL-line of the base, can the
1kHz sine waveform from
the Q1 collector be fed? Check the base TEL-line circuit
and RELAY control circuit.
OK
NG
Check whether there is the
1kHz sine waveform at Pin13
of IC1. Check IC1 and Pin13~14
peripheral circuits of IC1.
OK
NG
Check whether there is the
1kHz sine waveform at Pin9
of IC1. Check IC1 and Pin9~11
peripheral circuits of IC1.
OK
NG
TX output signal from the
base is detected by the liner
detector, can the 1kHz 3kHz
Dev. sine waveform be fed?
Check C65 and R51.
OK
NG
Check whether there is the
1kHz sine waveform at Pin16
of IC501. Check IC501 and Pin15~16
peripheral circuits of IC501.
OK
NG
Check whether there is the
1kHz sine waveform at Pin19
and 20 of IC501. Check IC501 and Pin17~20
peripheral circuits of IC501.
OK
NG
Check whether there is the
1kHz sine waveform during
for Pin1 and 2 of J501.
Check J501 and its soldering.
OK
NG
Check SP801 and WA801.