Press �3� key, check NG whether deviation of the TX data is app. 450kHz Dev.
Check whether there is a NG pulse data waveform at C630. OK Check handset RF unit.
Check whether there is NG a pulse data waveform at pin 40 of IC602. OK Check R654, R656, R701, C631 and C630.
Check IC602 and its periperal circuit.
OK Press �5� key, 914.880 NG MHz (400kHz~500kHz Dev.) 1mV output signal from RF jack is applied. Check whether the bell ring. OK Place the handset on the base to charge about 10 seconds, then connect again. Check whether there is NG the 450kHz waveform at C605. OK Check handset RF unit .
Check whether there is a NG 450kHz pulse waveform at pin 35 of IC602. OK
Check R620, R623, R697, C605, C631.
C h e ck w h e t h e r t h e NG voltage at R693 is more than 1V. OK Check R693.