CIRCUIT DESCRIPTION
5-6
Figure 5-2 UHF RF Board Block Diagram (Version C)
16.8 MHz
IF Amp
MMBR941
Antenna
Jack
Harmonic
Filter
8 ch
8 bit
DAC
1Kbit
EEPROM
Power Control
SPI
High Frequency Modulation
RX Band Select
64.455 MHz
15 KHz BW
I
L
R
MIXER
ADEX-10L
LO
BPF
1
C
2
D0
T/R PIN
Switch
SPI
LNA
MGA-71543
Switch
LNA Bypass
1
C
2
Switch
1
C
2
Switch
1
C
2
Switch
PA
Mitsubishi RA07M
DRIVER
Sirenza SGA 6589
VCO
444 - 509 MHz
(455 - 520 MHz)
VCO
380 - 445 MHz
(391 - 456 MHz)
Low Frequency Modulation
RF / Logic
Interface
SPI Addr
SPI
RF Out
1
20
19
18
17
16
15
14
13
12
11
10
9
8
7
6
5
4
3
2
SPI
MISO
SPI
MOSI
SPI
Clk
SPI
Addr1
SPI
Addr2
RF
Clk
RF
Data
RF
Frame
Sync
nTxEna
TxMod2
nTxNap
Temp
Lock
Detect
TxMod1
Lock
Enable
Unswitched
Battery
3.3V
5.5V
SPI
Addr3
SPI
VCO Select
RX LNA Bypass
TX Pwr Control
AT-267
Var Atten
1
C
2
1
C
2
Switch
380-444 MHz
(450-455 MHz)
Bandpass
Filters
444-470 MHz
(455-520 MHz)
1
C
2
1
C
2
Switch
380-444 MHz
(450-455 MHz)
Bandpass
Filters
444-470 MHz
(455-520 MHz)
Receiver Back End
AD9864
Fif = 2.1MHz
62.355 MHz
RF Out
SPI
64.455 MHz
15 KHz BW
PLL
RF2361
Switch
1
C
2
TX Pwr Control
rejection while providing minimal amplitude and
phase distortion within a 25 KHz bandwidth. Shields
installed around the crystal filter provide sufficient
isolation to meet the second image response specifica-
tions and minimize noise pickup by the impedance-
matching inductors (L1, L2, L3, L4 and L7.)
A transistor IF amplifier (Q1 and supporting
circuitry) is required to boost the signal strength,
thereby reducing the overall noise figure. The noise
figure, signal gain, intercept point, and power
consumption are optimized in this design. An addi-
tional two-pole 64.455 MHz crystal filter (U25) is
used to increase the adjacent channel rejection. An LC
circuit provides the required impedance matching
between the output of the IF filter and the input of the
backend chip (U11.)
Back End IC
An Analog Devices AD9864 IF Digitizing
Subsystem IC (U11) provides a variety of functions
for the receiver as follows:
Second Local Oscillator - A varactor-tuned tran-
sistor (Q2) oscillator is phase-locked to a fixed
frequency of 62.355 MHz for converting the first
IF of 64.455 MHz to a second IF frequency of 2.1
MHz. Phase Locked Loop circuitry inside of the
AD9864 operates with a phase-detector frequency
of 15 kHz.
Second Conversion Mixer and Filtering - A mixer
inside the AD9864 converts from the first IF of
64.455 MHz to the second IF of 2.1 MHz. External
filters (L29 and L30) provide IF bandpass filtering.
Additional filtering is provided by the inherent
operation of the sigma-delta analog/digital
converters.
Gain Control - This device provides up to 12 dB of
AGC range via a combination of analog and digital
controls. Additionally, there is a 16 dB attenuator
in the front end. The optimum settings are
controlled by the host microprocessor.
UHF RF BOARD (VERSION C)
Содержание 5100 Series
Страница 76: ...PARTS LIST 7 20 MP032 MP030 A200 Part of A200 Part of A200 MP031 MP033 MP034 A100 A030 EP031 J4 J3 EP030 6 ...
Страница 85: ...8 9 Version C Board see Section 1 13 VHF RF BOARD VER C LAYOUT ...
Страница 87: ...8 11 VHF RF BOARD SCHEMATIC VER B PAGE 2 OF 3 ...
Страница 88: ...8 12 VHF RF BOARD SCHEMATIC VER B PAGE 3 OF 3 ...
Страница 95: ...8 19 BOTTOM VIEW TOP VIEW Version C Board see Section 1 13 UHF RF BOARD VER C LAYOUT ...
Страница 105: ...8 29 BOTTOM VIEW TOP VIEW 700 800 MHZ RF BOARD VER C LAYOUT Version C Board see Section 1 13 ...
Страница 112: ...8 36 SEM Module 5500 120 LOGIC BOARD VER C SCHEMATIC PAGE 5 OF 11 ...
Страница 113: ...8 37 Analog Switch 5500 120 LOGIC BOARD VER C SCHEMATIC PAGE 6 OF 11 ...
Страница 118: ...8 42 5500 120 LOGIC BOARD VER C LAYOUT BOTTOM VIEW TOP VIEW Version C Board see Section 1 13 ...
Страница 127: ...8 51 5100 160 LOGIC BOARD VER B TOP VIEW 5100 160 LOGIC BOARD VER B BOTTOM VIEW Version with Motorola UCM ...
Страница 143: ...8 67 5500 420 USER INTERFACE BOARD VER C TOP VIEW Version C Board see Section 1 13 ...
Страница 144: ...8 68 5500 420 USER INTERFACE BOARD VER C BOTTOM VIEW ...
Страница 147: ...8 71 5100 410 USER INTERFACE BOARD VER A TOP VIEW Version w o encryption module Version A Board see Section 1 13 ...
Страница 148: ...8 72 5100 410 USER INTERFACE BOARD VER A BOTTOM VIEW Version w o encryption module ...
Страница 151: ...8 75 5100 450 USER INTERFACE BOARD VER B TOP VIEW Version with EFJ SEM Version B Board see Section 1 13 ...
Страница 152: ...8 76 5100 450 USER INTERFACE BOARD VER B BOTTOM VIEW Version with EFJ SEM ...
Страница 155: ...8 79 5100 460 USER INTERFACE BOARD VER B TOP VIEW Version with Motorola UCM Version B Board see Section 1 13 ...
Страница 156: ...8 80 5100 460 USER INTERFACE BOARD VER B BOTTOM VIEW Version with Motorola UCM ...
Страница 171: ...9 14 OBSOLETE VERSION 5100 410 USER INTERFACE BOARD VER A TOP VIEW Version A Board see Section 1 13 Revision 6 Board ...
Страница 172: ...9 15 OBSOLETE VERSION 5100 410 USER INTERFACE BOARD VER A BOTTOM VIEW Revision 6 Board ...
Страница 173: ...Part Number 001 5100 0017CD 12 04hph Printed in U S A ...