5. TROUBLE WITH INTERCOM MODE
5-1. The voice from the Base unit cannot be heard on the Handset.
Check whether there is an audio waveform on Pin 4 of IC7.
NG
Check MC251 and IC7.
OK
Check Pin 7 of IC6.
5-2. The voice from the Handset cannot be heard on the Base unit.
Check whether there is an audio waveform on Pin 1 of IC6.
NG
Check IC6.
OK
Check whether there is an audio waveform on Pin 15 of IC7.
