REXON LIS 2013 FuG 13b, Service Manual

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VR403
CTCSS ADJ.
VR402
DCS ADJ
VR501
Freq Error ADJ.
TP501:
VCO Pt
TP502
CT602
TX VCO ADJ
VR401
MOD DEV
ADJ.
VR404
Signalling
ADJ.
CT601
RX VCO ADJ
TP702
SQL Pt
VR701
SQL ADJ
• VCO ADJUSTMENT
Connect test point ( TP501 ) to multimeter for adjustment (ref alignment illustration ).
Set channel=509 , to adjust the CT601 obtain TP501 = 8. 6V for Rx VCO at receiver mode. to
adjust the CT602 obtain TP501 = 8. 5V for Tx VCO when PTT was activity
• FREQUENCY ERROR ALLGNMENT
Set channel= 509 wo , to adjust the VR501 to get transmission frequency= 87.255MHZ ±
200Hz when PTT was activity.
• DEVIATION ADJUSTMENT
Plug Mic jack from audio frequency generator.
Facilities setting: Audio generator=1KHz/80mV.
Set channel= 347 wu , To adjust VR401 to get maximum deviation ≥ 3.7KHz ≤ ±3.8KHz
when PTT was activity. Recheck Max. Dev ±3.5KHz .at the channel 509 wo .
1750Hz Adjustment: Set CH= 347 wu , press burst tone I key to adjust VR404 to get Max Dev
≥ ±3.5KHz ≤ ±3.8KHz and check frequency is below ±20Hz .
2135Hz checking: check burst tone II deviation is between ±3.5KHz to ±3.9KHz . and check
frequency error is below ±20H .
• HIGH POWER CHECKING
Set channel= 509 wu/wo , to check transmitter power is above 5W± 1W.
The transmitter’s power is above 5W and current is below 2.0 ampere by checking the other
channels.
• LOW POWER CHECKING
Confirming the transmission power between 1.0W to 1.3Watts at channel 347,416,486
and 509 with wu/wo. To make sure when battery voltage is below 6.4V , the transmitter
power was automatic changed to low power mode .
SENSITIVITY
To connect SINAD meter and 4 ohm dummy load
Apparatus setting: RF signal generator Frequency= 87.255MHz , level= 0.43uV ,
deviation= 2.4KHz , AF= 1KHz with CCITT filter
Set Channel= 509 wo , press “monitor” button, observing the SINAD meter is above 20dB
To confirm the channel= 347 wu/wo as well.
• AUDIO OUTPUT
Apparatus setting : RF signal generator level=1mV
Increase volume to get audio output level equal 1Vrms check audio distortion ≤ 3%.
Rotate the volume to make audio output distortion=7%, to check maximum audio output is
≥ 0.5Watt.
• SQUELCH ADJUSTMENT
Turn off the RF signal generator output and connect multimeter on test point (TP702).
open the squelch setting.
Set channel= 509 wo
Adjusting the VR701 obtain the SND equal with 16dB .
• RSSI SIGNAL LEVEL CHECK
Turn on the RF signal generator output , setting RF level= 10uV , make sure the signal meter is
full on LCD indicator.
• BATTERY LOW DETECTION
Connect to DC power supply.
Adjust DC IN=
6.4V , 1 battery bar is shown on LCD indicator when voltage in 6.4, increase
voltage to 6.6V , checking 2 battery bar shown on LCD indicator, increase to 6. 9V , checking 3
battery bar shown on LCD indicator, increase to 7.2V , that will show full battery bar on LCD
indicator.
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