Microwave Data Systems MDS 4310 - Figure 5-1.MDS 4310 Transceiver Block Diagram

MDS 05-2415A01, Rev. A THEORY OF OPERATION 5-7/8
U13
RSSI (J1-21)
MODEM RX LEVEL ADJUST
SQUELCH GATE
U26A
RSSI AMP
J1
4
AUDIO
INVERT
U3 C
U3A
U32
IF SUBSYSTEM
AUDIO BUFFER
FL1 A FL1 B
CRYSTAL FILTER
Z2
M1
HIGH IF AMP
Z1
Q1
RX
RF
AMP
ANTENNA
CONNECTOR
FWD PWR
(J7-
12)
HYBRID POWER
MODUL
E
DIRECTIONAL COUPLER
U40U33
FL2 FL3
U3 D
INVERTER
R41
SQUELCH
RX MUTE
U5 A
R25
VOX AF
(J6-17)
MODEM AF (J6-1)
RX AUDIO RUS (J1-11) (J1-10)
U6D
U5 D
COMPARATOR
U6B
U6C
EEPROM
NOISE AMP
NOISE RECT
TO OPTION 2
(DIAGNOSTICS BD.)
J5, J7
U6A
NOISE FILTER
REFL PWR
(J7-
3)
RADIO
ENABLE
(J1-12)
U36
SYNTHESIZER & PRESCALER
U16
MICROPROCESSOR
OUT-OF-LOCK DET. DRIVER
U28
A
R179COMP
HF AUDIO
LOOP FILTER
VCO
BUFFER
U41
2.5V
REF
R168
TRANSMIT DEV ADJ
U28C
U28B
LP
FILTER
LOOPBACK
TX AUDIO
U28D
14.85 MHz
TCXO
U1
3
LOW VOLTAGE
RESET
+ 5V
U5C
2.5
VDC
U3 8
U4
J4
Q1
9
U18
T1
DISCRIMINATOR
VCO SAMPLE
14.85 MHZ REF.
45 MHZ
ANTENNA SWITCH
FREQ.
TRIPLER
44.55 MHZ
Y1 3.6864 MHZ
BIAS
J
2
+13.5 V
IN
Q3
U44
A
R69
POWER
ADJUS
T
F1 4A
Z
4
C7
7
5
VDC
8
VDC
TX /
RX
U19
F
U19
A
MODEM ENABLE
(J6-18)
PTT
(J1-14)
U15Z
U26
B
MODEM TX AUDIO
TX AUDIO INPUT
(J1-9)
(J6-24)
MODEM PTT
PTT
(J1-16)
(J6-9)
U19
B
L17
U3
9
REGULATO
R
L3 2
L3
3
XMI
T
U2
9
O/L (J1-25)
U5
B
LED
FLASHER
U31
+5V
CR31
B
CR33
A
CR32
B
CR33
B
CR32
A
CR31
A
DC POWER
R D
T D
C D
TX
RS (RTS)
E N
J11 LEDS ENABLE
RT S (J6- 12)
CT S(J6- 6)
TD X(J1- 2)
RX D (J1- 3)
RT S(J1- 4)
CT S(J1- 5)
DC D (J1- 8)
TX CLK(J1- 15)
RX CLK (J1- 17)
EXT. CLK(J1- 24)
(J6- 23)
(J6- 21)
(J6- 20)
E N
J11
(OUT)
RS-232
ENABLE
(IN) TLL
ENABLE
L2 5
L 8
Z
5
C24 2
LINE
DRIVER
RECEIVER
Figure 5-1.MDS 4310 Transceiver Block Diagram