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4-4
RX AF CIRCUITS
• Left band
The demodulated AF signal from the AF SW (IC119) is
passed through the AF mute SW (IC111, pins 4, 3) and AF fi l-
ter (Q113), and then applied to the volume IC (IC110, pin 4),
which adjusts the AF signal in level.
The level-adjusted AF signal from the volume IC (IC110,
pin 11) is passed through the AF SW (IC109, pins 2, 1), which
selects the AF signal from Left and Right bands.
• Right band
The demodulated AF signal from the AF SW (IC119) is
passed through the AF mute SW (IC111, pins 8, 9) and AF
fi lter (Q112), and then applied to the volume IC (IC110, pin 3),
which adjusts the AF signal in level.
The level-adjusted AF signal from the volume IC (IC110,
pin 12) is passed through the AF SW (IC109, pins 3, 4), which
selects the AF signal from Left and Right bands.
When output from [EXTERNAL SPEAKER JACK1]
The output signal from the AF SW (IC109) is passed through
the AF MUTE SW (Q104 and Q105), and applied to the AF
AMP (IC105, pin 1).
The amplifi ed AF signal is applied to the internal speaker
(CHASSIS: SP1) or an external speaker, through [EXTER-
NAL SPEAKER JACK1] (J101).
When output from [EXTERNAL SPEAKER JACK2]
The output signal from the AF SW (IC109) is passed through
the AF MUTE SW (Q106), and applied to the AF AMP (IC106,
pin 1).
The amplifi ed AF signal is applied to [EXTERNAL SPEAKER
JACK2] (J102).
AF
AMP
SP1
AF
AMP
LPF
BUFF
J102
J101
BUFF
BUFF
AFSW
FIL
SP
MUTE
VR
ELEC.
MUTE
SP
AF
DETMUTE
AF
FIL
SP
MUTE
BTAF
Optional module
RPT
RPT
SW
IC106
Q106
IC105
Q104
Q105
IC109
IC107
IC104
IC103
Modulation circuit
TX AF circuit
2nd IF circuit (Left band )
2nd IF circuit (Right band )
IC110
IC111
Q112,Q139
Q113,Q140
IC103
IC103
L_RMUTE
R_RMUTE
• RX AF CIRCUITS