Panasonic KX-TS3282B - Paging All Extensions; Transferring an External Call to Another Extension

12.8.2. Data Communication Block
1. Data Transmission
The oscillated waveform of 455 kHz (A) at pin 10 of IC701 becomes
the tone burst signal (C) at pin 12 of IC701 by the data signal (B)
from pin 31 of the microcomputer IC801. And then it passes the
amplifier mixed with the audio FM signal and is transmitted to
the telephone line via the transformer (T701).
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