Figure 6-11. Vhf (146-174 Mhz) Audio Circuitry Schematic Diagram - Motorola EP450 Service Manual

VHF 146-174 MHz PCB 8486342Z13-C Schematic Diagrams, Overlays, and Parts Lists
R516
NU
C512
6.8pF
R512 150K
U510-1
LM2904
R511
2 8
R513
DEMOD
1
100K
3
4
5V_A
C511 C513
220pF
220pF
R518
220K
C519
R519
100K
1uF
VS_AUDIO_SEL
VS_GAIN_SEL
PWR_SET
VOX
BW_SEL
CH_ACT
SQ_DET
LSIO
HSIO
ASFIC_CS
SPI_CLK
SPI_DATA_OUT
VHF UHF
R513 Not Placed 100k
R515 Not Placed 0
R516 Not Placed Not Placed
R517 0 Not Placed
HKLN4216A
C514
R522
16pF
100K
R514
5V_A
100K
1
Q520 5
IMX1
C518
6
8
6 C460
R515
0.1uF
7
5
4 U510-2 0.1uF
LM2904
R520
R521
NU 100K
R517
3V_A
3V_A R460
24K
C451
0.1uF
C452
C454
5V_A
0.1uF C453
R462
0.1uF
24K
4.7uF
C455
10 V
.022uF
3V_A
NC
13 GCB2 48
MICEXT
14 GCB1 47
GNDRC
15 GCB0 46
MICINT
16 CHACT 45
VDDRC
17 SQDET U451 44
TXSND
18 LSIO 43
RXRTN
30C53
19 HSIO 42
AUXTN
20 CSX 41
AUDIO
21 40
CLK MOD
22 DATA 39
RXSND
38
23 GND GCB5
NC
37
SYN
GCB4
24 LCAP
C456 C457
NC
0.1uF 0.1uF
C458
0.1uF
R451
47K
3V_A
3V
E451
3V 16_8_MHZ
BK1005HM471 C459
F1200
0.1uF
uP_CLK
5V_ B
E452
BK1005HM471
5V 5V_A
E453
5V
Q481
BK1005HM471
C497
Not_Placed:NU 1
0.1uF
R486
100K
Not_Placed:NU
R523
10K Audio
4
2 Q520
IMX1
3
OPT_RX_AUD_SEND_DETECTO R
OPT_RX_AUD_RETURN
OPT_RX_AUD_SEND_UNMUTED
OPT_TX_AUD_FLAT_RETURN
OPT_TX_AUD_SEND
OPT_TX_AUD_RETURN
C461
1000pF
3V
C467
C462
C463
1200pF
0.1uF 0.1uF
R474
330
R464 R463
30K 24K
C465
C464 C471
R476
0.1uF 1000pF 2.2uF
100K
2
C472
0.1uF
A_MOD_OUT
MOD_OUT
C466
NU
SW_B+
C493
1000pF
5V_B
R487
C499
0
5V_B
82pF
C483
R484
C481
C482 2 8 0.1uF
2.2K R491 R492
.01uF
.01uF 1
3
Not_Placed:NU 0 24K
4
C484
Not:Placed:NU
U480-1
2 3 R490
.033uF
Not_Placed:NU
2.2K
LM2904
Not_Placed:NU
Not_Placed:NU
3
R483
R485 100K
1
150K Q482
Not_Placed:NU
2
Q490 Not_Placed:NU
UMG5
6
1
5V_B U511
2
UMG5
3
6
4 1
R488
330K
2
3 R495
4
C490
5.6K
470pF
C498
1uF
VR471
R470
2.2K
3V_A
NC
R480
0
R472 1 R473
4
680
680
VR472
C470 D471
R471 2
5
Q472
2.2K
0.1uF
Q471
6 3
6
1
NC
C477
2
5V
0.1u F
3
4
R255
3.9K
1%
4 BATT_CHARGE
1 R475
180K
D470 OPT_MIC
R477
L471
5
Q470
390nH
2.2K
NC
C474 C473
150pF SCI
6 3 150pF VR473
20V
MMBZ5250B
NC
NC
EXT_MIC_PTT
VR474
MMBZ5250B
C475
VR475
R479 15V MMBZ5245B 20V
100K
.022uF
J470-1
R478
1
2.2K
C478
C476
2
.022uF 150pF
C494
R494
MICROPHONE
330K
2.2uF CONNECTOR
DC Level 0.3 - 0.4 V low
6
C488
C480
Supply = 7.42 R469
VCC
1/2 Supply = 3.22 470pF
U490
10
0.1uF
TDA854
1
MODE
5
3
INPOS OUTNEG
2 8
SVR OUTPOS
4
INNEG
C489
C479
GN D 1
470pF
7
R496
150pF
C492
10K
R497
Not_Placed:NU
10uF 1MEG 5V_B
Not_Placed:NU
C496
R499
D491
8 6 270K
R498
1uF
7
Not_Placed:NU
5
47 K
4
C495
R489
U480-2
1uF
91K
NC LM2904
Not_Placed:NU
Not_Placed:NU
Not_Placed:NU

Figure 6-11. VHF (146-174 MHz) Audio Circuitry Schematic Diagram

6-13
RESET
BOOT_ENA
J471
ACCESSORY
CONNECTOR
4 S2
5 S4
6 S3
7 S1
2 M2
3 M3
1 M1
J491-1
INTERNAL
SPEAKER
1
2
3 J491-3
4 J491-4
November 24, 2003