Toshiba FT-7807R, Service Manual

Page: 17 / 52

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7. The voice of the caller cannot be heard (incoming call).
Check the handset RX SP
out.
Check the handset RX
sensitivity.
Check the handset RX RF
and mixer circuit (around
Q501) as well as FT501 and
FT503.
In the handset, with the SG
standard modulation of
1kHz 3kHz deviation and
input signal of 1mV, can
the sine wave be seen at
Pin 25 of IC504?
Then, can the sine wave
be seen at Pin 24 of IC504?
Then, can the sine wave be
seen at Pin 46 of IC504
and C515?
Then, can the sine wave of
the handset SP Limit be
seen?
SP of handset is defective.
Check the handset IF
circuit (around Pins 26~29
of IC504).
Check circuit around Pin 24
of IC504.
Check around Pins 44~46,
52 of IC504.
The wire connecting the
handset SP is cut.
NG
OK
OK NG
OK
OK
OK
OK
NG
NG
NG
NG
NG
Check the base TX power.
Check the base TX
modulation sensitivity.
SP of handset is defective.
Check the base TX circuit
using voltage chart.
Check the base TX AF
circuit (around Pins 17,
19~21 of IC1).
NG
OK
OK