Modem Circuit Operation - Panasonic KX-MB1520FX7 Service Manual

6.3.3.

Modem Circuit Operation

The modem (Included IC300) has all the hardware satisfying the CCITT standards mentioned previously.
ALL processing is controlled by the SOC (IC300) according to CCITT procedures.
This modem (Included IC300) has an automatic application equalizer. With training signal 1 or 2 at the time of G3 reception, it can
automatically establish the optimum equalizer.
Facsimile Transmission/DTMF Line Send
The digital image data sent on ATXD line from modem (Included IC300).
AFE IC (IC200) and analog circuit to the telephone line.
Facsimile Reception
The analog image data which is received from the telephone line passes through analog circuit and enters AFE IC(IC200). The
signals are changed to digital data in AFE IC and IC300. In this case, the image signals from the telephone line are transmitted
serially. Here, the internal equalizer circuit reduces the image signals to a long-distance receiving level. This is designed to cor-
rect the characteristics of the frequency band centered around 3 kHz and maintain a constant receiving sensitivity.
In this case, the image signals from the telephone line are transmitted serially.
Busy/Dial Tone Detection
The path is the same as Facsimile Reception.
Call Tone Transmission
This is the call signal which is generated the SOC (IC300) and sent to the speaker.
KX-MB1520FX7/KX-MB1520FX8/KX-MB1520FXW/KX-MB1530FX7/KX-MB1530FXW
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