Toshiba FT-8259, Service Manual

Page: 15 / 60

16
3. The base and handset cannot be connected.
Check whether the base
is able to set in the test
mode 1.
OK
NG
A
Check IC14 and its
peripheral circuit.
Check base RF unit.
NG
Check the TX POWER
and the TX FREQUENCY
on the base unit.
OK
NG
Check base RF unit.
Set the base in the test
mode 3, check whether
deviation of the TX data
is app. 8 kHz Dev.
OK
NG Check whether there is a
250 Hz data waveform at
“MOD” of RF unit. Check RT2, R69, R70,
R71, R72, R115, C56
and C84. NG
OK
Check base RF unit.
Set the base in the test
mode 8, 903.002467
MHz (250 Hz ±8 kHz
Dev.) 1mV output signal
from RF jack is applied.
Can the INTCOM LED
be lighted?
OK
NG Check whether there is a
250 Hz data waveform at
pin 9 of IC181. Check IC181, Q181 and
their peripheral circuit. NG
OK
Check whether there is a
250 Hz data waveform at
the Q3 collector. Check RT1, Q3 and their
peripheral circuit. NG
OK
Check whether there is a
250 Hz data waveform at
pin 54 of IC14. Check R261, IC4 and
their peripheral circuit. NG
OK
Check IC14 and its
peripheral circuit.
Check whether the
handset is able to set in
the test mode 1.
OK
NG Check IC603 and its
peripheral circuit.
Check the TX POWER
and the TX FREQUENCY
on the handset unit.
OK
NG
Check handset RF unit.
OK