Theory of Operation:
Main Board
3-7
Figure 3-6. Receiver Block Diagram (UHF2)
Figure 3-7. Receiver Block Diagram (VHF)
Figure 3-8. Receiver Block Diagram (700/800 MHz)
Antenna
Switch
15 dB Step
Attenuator
UHF2
UHF2
IF Filter
DIG_CTRL_ATTH Rx
LO
To GPS
Diplexer
SSI
18Mhz
CLK
Abacus III
ABACUS III
Dec.
Filter
ΣΔ
ADC
2nd
LO
LO CLK
Antenna
Switch
Harmonic
Filter
15 dB Step
Attenuator
VHF
VHF
IF Filter
DIG_CTRL_ATTH
Rx LO
To GPS
Diplexer
SSI
18Mhz
CLK
Abacus III
ABACUS III
Dec.
Filter
ΣΔ
ADC
2nd
LO
LO
CLK
15 dB Step
Attenuator
Antenna
Switch
SW
DIG_CTRL_ATTH
700
800
700
800
Rx LO
IF Filter
To GPS
Diplexer
SW
SW
SW
SSI
18Mhz
CLK
Abacus III
ABACUS III
Dec.
Filter
ΣΔ
ADC
2nd
LO
LO
CLK
Harmonic
Filter
Summary of Contents for Astro APX 3000
Page 1: ...APXTM TWO WAY RADIOS APX 3000 DETAILED SERVICE MANUAL ...
Page 2: ......
Page 4: ...Notes ...
Page 6: ...vi Document History Notes ...
Page 10: ...x Table of Contents Notes ...
Page 12: ...xii List of Tables Notes ...
Page 18: ...xviii List of Figures Notes ...
Page 22: ...xxii CommercialWarranty Notes ...
Page 46: ...3 20 Theory of Operation Main Board Notes ...
Page 84: ...3 58 Theory of Operation Bluetooth Notes ...
Page 208: ...6 64 Troubleshooting Waveforms LF CW on Spectrum Analyzer Notes ...
Page 222: ...7 14 Troubleshooting Tables List of Board and IC Signals Notes ...
Page 282: ...8 60 Schematics Boards Overlays and Parts Lists Main Board Block UHF1 84012513001_A Notes ...
Page 390: ...8 168 Schematics Boards Overlays and Parts Lists Main Board Block VHF 84012512001_A Notes ...
Page 456: ...9 8 Debugging Fixture Powering up Covert Board Notes ...
Page 468: ...Glossary 10 Glossary Notes ...
Page 472: ...Index 4 Index Notes ...
Page 473: ......