Poor Rx Sensitivity Or No Rx Audio (136-174 Mhz)-Part 1 Of 2 - Motorola ASTRO Digital XTL 5000 Detailed Service Manual

Troubleshooting Charts: Flowcharts
5.6.1 Poor RX Sensitivity or No RX Audio (136–174 MHz)—Part 1 of 2
Go to digital section
or
software problem
Go to FGU section
Software problem
Figure 5-5. Poor RX Sensitivity or No RX Audio (136–174 MHz)—Part 1 of 2
6881096C74-B
Yes
Pre-amp mode
easure 2.85V on
RF_ATT2_A at
C3288
Is the level
No
2.85V
?
Yes
easure 9.3V
on LNAs
Does a
level of 9.3V
No
exist on
L3257,L3262,
L3400
?
Yes
easure 2.85V on
RF_ATT1_A at
C3236
Yes Is the level
2.85V
?
No
easure LO power
of 20dBm at
TP6771
START
Radio is in
Pre amp
mode
Is
level of 9.3V
No
receiver in
L3262,L3400
?
Is LO power
No
Go to FGU section
20dBm
?
Yes
1
Does a
No Go to FGU
exist on
section
?
Yes
AEPF-27875-O_VHF
May 25, 2005
5-15