16.2. Power Supply Circuit
The power supply to the CPU (Digital, Analog) and RF IC from AC Adaptor (+12V) is shown in the diagram below.
The base unit power supply is DC12V. The handset´s power is supplied from 3.6V battery (Nickel-Cadmium battery) which is
installed in the handset.
Power supply for transmitter is turned on by a press of "Talk" key on the handset. During the stand-by mode, the unit stops
transmitting but receive thhe signal.
Also during on-hook condition (the handset is placed on the base unit), backup power for memory of the last dialed number is
supplied through the battery (3.6V nickel-cadmium in the handset). The memory of this unit is not backed up by the curreent
from the telephone line.
The base unit DC power supply is regulated by Q18, the CPU power is regulated by Q19. The Q8, detects AC Adaptor
powerfailure and maintains the unit cecutiry cord;
Fig. 1
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KX-TC1205RUB / KX-TC1205RUW / KX-TC1205R US / KX-TC1205RUF