Operation Manual

5-5
Maintenance
SequenceSequence
SequenceSequence
Sequence
ConditionCondition
ConditionCondition
Condition
Adjust PointAdjust Point
Adjust PointAdjust Point
Adjust Point
TT
TT
T
arget Levelarget Level
arget Levelarget Level
arget Level
1 CH16 (156.800 MHz) SG output: 10uv L16, L18-L22 Maximum SINAD
2 CH60 (156.025 MHz) SG output: 0.6uv L16, L18-L22 Over 12dB SINAD
3 WX0 (163.275 MHz) SG output: 0.6uv L16, L18-L22 Over 12dB SINAD
5.3.5 RF Sensitivity Adjustment (All Channel
Receiver)
1) Connect a RF Signal Generator (SG) to the antenna connector and a
SINAD meter to the AF out 1 (pin 10 of J2).
2) Set up the SG at 1 kHz+/-3 kHz deviation and adjust L16, L18-L22 on the
RF PCB as follows.
Caution: Do not tune L17.
3) After alignment, check at Channel 60 and Weather Channel 0 for 12dB
SINAD minimum with 0.35 uV output from SG.
5.3.6 RF Sensitivity Adjustment (CH 70 Receiver)
1) Set up the SG to CH70 (156.525 MHz) at 1 kHz +/-3 kHz deviation.
2) Connect the SINAD Meter to the AFout2 (pin 16 of J2) on the RF PCB.
3) Adjust L25-L29 on the RF PCB to get the best SINAD (over 12 dB
SINAD) when SG output is .06uV.
4) Check using 0.35 uV SG input level for 12dB SINAD minimum per spec.
5.3.7 Weather Alert Decoder Adjustment
1) Connect the SG to the antenna connector.
2) Set up CH WX1 (162.550 MHz) with 1050 Hz +/-3 kHz deviation.
3) Connect the DC Volt Meter to TP2 on the RF PCB.
4) With VR5 fully clockwise, turn counter-clockwise and note its position
when TP2 voltage changes from 5.0 VDC to 0 VDC.
5) Continue to turn VR5 CCW until TP2 voltage changes from 0 VDC to 5
VDC.
6) The final setting for VR5 is for 0 VDC between these two points.
RAY230_sect5.p65 7/13/2001, 1:43 PM5