6815854H01-A
June 15, 2005
Troubleshooting Charts:
Flowcharts
5-25
5.6.14 Poor RX Sensitivity or No RX Audio (380–470 MHz and 450–520 MHz)—Part 1
of 2
Figure 5-16. Poor RX Sensitivity or No RX Audio (380–470 MHz and 450–520 MHz)—Part 1 of 2
Poor Rx
Sensitivity or no
Rx audio
Measure Transceiver
12dB Sinad by injecting
signal at antenna port
Yes
Yes
3kHz FM Deviation
1kHz Audio tone
12 dB Sinad
Sensitivity
< - 117.5 dBm Std.
<-121dBm w/pre-amp
Check RF level at
Mixer LO injection port
at R5388
Receiver
is working
properly
No
Yes
Good?
1
Check preselector circuit and
tuning control voltage.
Tuning control voltage should be:
~ 2V for 380 MHz and
~ 8V for 470 MHz (UHF Range 1)
~ 2.5V for 450 MHz and
~ 7.5V for 520 MHz (UHF Range 2)
No
Yes
LO level
at + 24dBm?
Check RX front-end
tuning
Check Receiver
VCO troubleshooting
flowchart
(LO injection section)
Retune Front-End
filters using tuner
and help screens
No
Yes
Содержание XTL 1500
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Страница 49: ...June 15 2005 6815854H01 A 2 12 Product Overview Controller Section Notes ...
Страница 161: ...June 15 2005 6815854H01 A 4 36 Troubleshooting Procedures Power Amplifier Procedures Notes ...
Страница 225: ...June 15 2005 6815854H01 A 5 64 Troubleshooting Charts Flowcharts Notes ...
Страница 429: ...8 2 Flex Cable Pin Out Lists Flex Cables June 15 2005 6815854H01 A Notes ...
Страница 441: ...June 15 2005 6815854H01 A Glossary 10 Notes ...
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