Panasonic KX-FT931LA-B Service Manual page 39

6.7.6. Calling Line Identification Circuit
1. Function
This unit is compatible with the Caller ID service offered by your local telephone company. To use this feature, you must sub-
scribe to a Caller ID service. The data for the caller ID from the telephone exchange is sent during the interval between the
first and second rings of the bell signal. The data from the telephone exchange is a modem signal which is modulated in an
FSK (Frequency Shift Keying) format. Data "0" is a 1200 Hz sine wave, and data 1 a 2200 Hz sine wave.
There are two type of the message format which can be received:i.e.the single data message format and multiple data mes-
sage format.
The multiple data format allows to transmit the name and data code information in addition to the time and telephone number
data.
When there is multiple data in the unit, the name or telephone number are displayed.
2. Circuit Operation:
The caller ID signal input from TEL LINE is processed with IC5.
Refer to Sgnal Route (P.107) for the route of caller ID signal.
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KX-FT931LA-B