Diagrams; Block Diagram - Base Unit Section (1/2); Block Diagram - Base Unit Section (2/2) - Sony SPP-A941 Service Manual

5-1. BLOCK DIAGRAM – BASE UNIT Section (1/2) –
MIX, OSC, LIMITER AMP, DET
U1
926.25MHz
926MHz
MIX
SAW
A1IN OUT
B.P.F. RF AMP
FILTER 3 MIXER 5
F2 Q2
F3
ANT1
(ANTENNA)
LOCAL OSC
BUFFER
26
903MHz
B.P.F. TX AMP
F1 Q1
RX VCO
Q9
PLL
U10
CP2
RX SYSTEM
14
PLL CIRCUIT
CP1
TX SYSTEM
3
PLL CIRCUIT
CONTROL REFERENCE
CIRCUIT DIVIDER
7 6 8 11
• SIGNAL PATH
: RX
: TX
: BELL
05
SECTION 5

DIAGRAMS

L12
10.7MHz
LIM1 LIM1 F4
F5 LIM2
IN OUT 10.7MHz
10.7MHz IN
LIMITER LIMITER
9 22 20
AMP AMP
RSSI
10
TX VCO
Q8
CARRIER
DETECT AMP
Q3, 4
18
FIN2
16
FIN1
1
SYSTEM CONTROLLER
U1 (1/2)
C15
TX
FREQUENCY
OSC
26 OSC2
Q4
27 OSC1
X1
4MHz
10 PLL EN
13
EEP/PLL CLK
11 EEP/PLL DATA
12 EEP DI
9
EEP CS
3 2 4 1
EEPROM
U3
– 17 –
C99
QUAD-VOLTAGE
16
DEM FIL2 FIL2
OUT IN OUT
DE- BUFFER
15 2 1
MODULATOR U5 (3/4)
LOW-PASS
FILTER
LOW-PASS
FILTER
COMPRESSOR, EXPANDER, NOISE GATE
U5 (4/4)
LOW-PASS
FILTER
FIL1 FIL1
DATA/AUDIO
OUT IN
3 4 ADDER
U5 (2/4)
TX MUTE
Q6
RX DATA 25
TX DATA 24
MUTE 16
DTMF
LOW-PASS FILTER
U5 (3/4)
SP1
50
HOOK ON/OFF
DETECT
Q1
LED1
IN USE
LED DRIVE
Q12
17
OFF HOOK
RINGER DET 20
VR1
DEMOD
AUDIO LEVEL
EXP
PRE
OUT
NF
DE- EXPANDER
23 20
EMPHASIS CIRCUIT
PREAMP
U4
COMP
OUT
PRE COMPRESSOR
+ +
5
EMPHASIS CIRCUIT
VR2
MOD
DEVIATION
6 15 16
LIFPOUT/
39
MIC1 25 MIC+
DTMF
MIC
26
MIC–
SPEAKER AMP
23 LIFMIN2 36
SPK+
U6
56
TAD
U1 (1/2)
20 45 31
LINE DC
COMPARATOR
LEVEL
SHIFT U2
Q2
D9 – 12
RECT
T1
LINE
TRANSFORMER
D9
HOOK ON/OFF
U7
D10
– 18 –
SPP-A941
RIN
+
19
– RO1
18
+
RO1 AMP
BUFFER
Q17
MIC
AMP
MIC NF
10
9
D12
D11
J7
LINE
RINGER
DETECT
U8