Panasonic KX-TD7895 - Digital Spread Spedtrum Telephone, Service Manual

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telephone line. Via the following path:
RF unit IC106(24) IC106(11) C153 R193 C162 Q115 C159 R202
C110 Q103 R106 C187 Q108 Q100 D101 T/R
7.1.6. DTMF SIGNAL
When the DTMF data from the portable unit is received, the DTMF signal is output from the
IC105(23) and sent to the line.
7.1.7. LINK MODE AND HOOK
Normally the line mute is controlled by LPR(IC105). When wearing the headset, it is controlled
by CPU(IC107) in the auto answer mode only. Also the Hook is controlled by CPU(IC107) in the
auto answer mode only.
Line Mute Control
STANDBY TALK
[Normal]
IC105(42) H L
IC107(45) H H
[Auto
Answer]
IC105(42) H
H
IC107(45) H L
IC112(4) (AND)
H : Line Mute
Hook Control