Troubleshooting Charts:
RX RF Failure
5-37
RX RF Failure – Page 3
2
Remove shield, SH3.
Measure RF levels at first
preselector filter and
compute filter loss.
VHF: Input side of C301 &
output side of C307.
Loss < 2 dB?
Check components
and replace defective
parts.
No
Measure RF levels at LNA
and compute LNA gain.
VHF: Input side of C311 and
output side of R307.
Gain about
18 dB?
Check LNA:
Check DC bias voltages of
U302 at the base (pin 1) &
collector (pin 3).
No
Is base voltage =
0.796 V? Collector
voltage = 1.563 V?
Replace
U302
Is base voltage = 1.017 V?
Collector voltage =
0.796 V? Emitter
voltage = 1.566 V?
Replace
Q302
Check DC input line voltages
and visually inspect and
replace defective
components if needed.
No
Yes
No
Yes
Measure RF levels at second
preselector filter and compute
filter loss.
VHF: input side of C318 & output
side of C326.
Loss < 6 dB?
Check components
and replace defective
parts.
No
Yes
8
Yes
Yes
Check DC bias voltages of
Q302 at the base (pin 2 or
5), collector (pin 3) & emitter
(pin 4).
Note:
RF Test frequency used:
VHF: 154.275MHz
UHF1: 424.975MHz
UHF2: 485.075 MHz
700: 769.0625MHz
800: 860.0625MHz
Measured with a high impedance probe for relative comparisons and troubleshooting only.
Actual S21 gain or loss may differ if the test point is not 50 ohms.
Содержание APX 6000
Страница 1: ...APX TWO WAY RADIOS APX 5000 APX 6000 APX 6000XE SRX 2200 Detailed Service Manuals ...
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Страница 6: ...iv Document History Notes ...
Страница 20: ...xviii CommercialWarranty Notes ...
Страница 26: ...2 4 Radio Power DC Power Routing VOCON Board Notes ...
Страница 100: ...3 74 Theory of Operation Bluetooth Notes ...
Страница 172: ...5 66 Troubleshooting Charts PA Failure Notes ...
Страница 176: ...6 4 Troubleshooting Waveforms Clocks 6 2 2 4 MHz Clock Trace 1 Trace recorded at R6113 Figure 6 2 4 MHz Clock Waveform ...
Страница 183: ...Troubleshooting Waveforms Audio SSI 6 11 6 3 4 BCLK Trace 1 Trace recorded at R6107 Figure 6 9 Audio SSI BCLK Waveform ...
Страница 185: ...Troubleshooting Waveforms RX SSI 6 13 6 4 2 DA Trace 1 Trace recorded at R1005 Figure 6 11 RX SSI DA Waveform ...
Страница 186: ...6 14 Troubleshooting Waveforms RX SSI 6 4 3 FSYNC Trace 1 Trace recorded at R1004 Figure 6 12 RX SSI FSync Waveform ...
Страница 188: ...6 16 Troubleshooting Waveforms TX SSI 6 5 2 DA Trace 1 Trace recorded at R1017 Figure 6 14 TX SSI DA Waveform ...
Страница 189: ...Troubleshooting Waveforms TX SSI 6 17 6 5 3 FSYNC Trace 1 Trace recorded at R1007 Figure 6 15 TX SSI FSync Waveform ...
Страница 190: ...6 18 Troubleshooting Waveforms SPI 6 6 SPI 6 6 1 CLK Trace 1 Trace recorded at R1003 Figure 6 16 SPI CLK Waveform ...
Страница 191: ...Troubleshooting Waveforms SPI 6 19 6 6 2 MOSI Trace 1 Trace recorded at Pin 31 of J1001 Figure 6 17 MOSI Waveform ...
Страница 192: ...6 20 Troubleshooting Waveforms SPI 6 6 3 MISO Trace 1 Trace recorded at Pin 29 of J1001 Figure 6 18 MISO Waveform ...
Страница 193: ...Troubleshooting Waveforms SPI 6 21 6 6 4 CS Trace 1 Trace recorded at R1018 Figure 6 19 CS Waveform ...
Страница 195: ...Troubleshooting Waveforms I2C BUS 6 23 6 7 2 SCL 5V Trace 1 Trace recorded at R2204 Figure 6 21 I2C Bus SCA 5V Waveform ...
Страница 196: ...6 24 Troubleshooting Waveforms I2C BUS 6 7 3 SDA Trace 1 Trace recorded at R6209 Figure 6 22 I2C Bus SDA Waveform ...
Страница 200: ...6 28 Troubleshooting Waveforms USB 6 10 USB 6 10 1 D Trace 1 Trace recorded at TP F_GCAI_USB Figure 6 26 USB D Waveform ...
Страница 201: ...Troubleshooting Waveforms USB 6 29 6 10 2 D Trace 1 Trace recorded at TP F_GCAI_USB Figure 6 27 USB D Waveform ...
Страница 203: ...Troubleshooting Waveforms UART 6 31 6 11 2 TX Trace 1 Trace recorded at TP F_BOOT_TX Figure 6 29 UART TX Waveform ...
Страница 205: ...Troubleshooting Waveforms SDRAM 6 33 6 12 2 CLKX Trace 1 Trace recorded at TP6308 Figure 6 31 SDRAM CLKX Waveform ...
Страница 250: ...6 78 Troubleshooting Waveforms LF CW on Spectrum Analyzer Notes ...
Страница 276: ...7 26 Troubleshooting Tables List of Board and IC Signals Notes ...
Страница 300: ...8 24 Schematics Boards Overlays and Parts Lists Transceiver RF Boards VHF Notes ...
Страница 336: ...8 60 Schematics Boards Overlays and Parts Lists Transceiver RF Boards UHF1 Notes ...
Страница 378: ...8 102 Schematics Boards Overlays and Parts Lists Transceiver RF Boards 700 800 MHz Notes ...
Страница 432: ...Glossary 10 Glossary Notes ...
Страница 437: ......