Panasonic KX-F900 Service Manual page 182

KX-F900
Circuit Diagram
IC202 EXPANDER
3KHz LPF
RF Part -_
AF __ VR202
Receive level adjust
[__ IC208
I I I _ I
Sidetone
_ ___JcontrollC
Gain control R I :0_38
R265
RX VOL
SPK MUTE (_)
SPEAKER
SPK MUTE
(5) Sending Signal
The audio signal from the microphone is amplified by Q208 and then passes through a limiter, mute circuit,
compander, and 3 kHz LPF built into IC202. It is then mixed with the TX DATA signal from the CPU, the
maximum modulation is adjusted by VR201, and input to the modulator in the RF block.
Circuit Diagram
R217
CPU R250
TX DATA _ T
CPU MIC MUTE ..LR229
LIMITER H_'ICOMPANDER_ _ :
i
=
i
=
IC202
i
............................................................. i
,_]_o RF Part
MOD
VR201
MAXIMUM
Deviation adjust
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