Set the handset in the NG test mode 3, check whether deviation of the TX data is app. 9.0 kHz Dev.
Check whether there is a NG 250 Hz data waveform at RT602. OK Check handset RF section.
Check R668, R712, R713, R716, R717, C719, C748 and RT602.
OK Set the handset in the NG test mode 6, 926.997467 MHz (250 Hz ±8 kHz Dev.) 1mV output signal from RF test point is applied. Check whether the bell ring. OK Place the handset on the base to charge about 5 seconds, then connect again. Check whether the 250 NG Hz data waveform from Pin 9 of IC603 is fed. OK Check IC603 and its peripheral circuit. OK NG Check handset RF section.
Check whether there is a NG 250 Hz data waveform at Pin 10 of IC602. OK Check whether there is a NG 250 Hz data waveform at Pin 40 of IC608. OK Check IC608 and its peripheral circuit.
Check IC602 and its peripheral circuit.
Check R648, R649, IC602 and their peripheral circuits.
