3-72
Theory of Operation
: Global Positioning System (GPS)
• The GPS TX output (U2206 pin J6 for MHLN6977 and pin F5 for MHLN7035), connects to
OMAP UART2_RX (U6302 pin R9) – TP2205
• The GPS RX input (U2206 pin K6 for MHLN6977 and pin E3 for MHLN7035) connects to
OMAP UART2_TX (U6302 pin M18) – TP2206
NOTE:
• SAW filter FL1301 is used by all APX7000/ APX 7000XE radios with expander board
HLN7035A.
.
Figure 3-55. GPS Block Diagram (VHF/700–800 MHz) – Expander Board MHLN6977A
RF-Vocon-Exp
Interconnect
RF Board
Ant
LNA
3.0V
Unbalanced
SAW
LNA
GPS_2.8V
LNA Enable
3.6V
(VSW_3.6)
2.8V
1.8V
1.2V
GPS_2.8V
[OMAP 1710]
UART2_Rx
(R9)
RF Vcc I/O Vcc Core Vdd
UART2_Tx
(M18)
IO74
(E2)
IO91
(D12)
FDOUT
(H1)
RFA_INP
(A5)
RFA_INM
(B5)
REF_CLK_IN
(D4)
MISO_TXD0
(J6)
MOSI_RXD0
(K6)
LOW_REF_CLKI
(D1)
NRESET
(C1)
SiRF GSCi-5001
GPS IC
Reset
32kHz RTC
GPS Rx
GPS Tx
TCXO
26MHz
<0.5ppm
External Regulators
Expansion Board
Balanced
SAW
Summary of Contents for ASTRO APX 7000
Page 1: ......
Page 4: ...iv Document History Notes ...
Page 24: ...2 4 Radio Power DC Power Routing VOCON Board Notes ...
Page 98: ...3 74 Theory of Operation Global Positioning System GPS ...
Page 163: ...Troubleshooting Charts PA Failure 5 59 ...
Page 164: ...5 60 Troubleshooting Charts PA Failure ...
Page 276: ...7 58 Troubleshooting Tables List of Board and IC Signals Notes ...
Page 318: ...8 42 Schematics Boards Overlays and Parts Lists Transceiver RF Boards VHF 700 800 Notes ...
Page 380: ...8 104 Schematics Boards Overlays and Parts Lists Transceiver RF Boards UHF1 700 800 MHz Notes ...
Page 432: ...8 156 Schematics Boards Overlays and Parts Lists Transceiver RF Boards UHF1 VHF Notes ...
Page 458: ...8 182 Schematics Boards Overlays and Parts Lists Transceiver RF Boards UHF1 UHF2 Notes ...
Page 498: ...8 222 Schematics Boards Overlays and Parts Lists Transceiver RF Boards UHF2 700 800 MHz Notes ...
Page 546: ...8 270 Schematics Boards Overlays and Parts Lists Transceiver RF Boards UHF2 VHF Notes ...
Page 606: ...8 330 Schematics Boards Overlays and Parts Lists VOCON Boards Notes ...
Page 638: ...Glossary 10 Glossary Notes ...
Page 643: ......