Warping Failure Troubleshooting - Motorola MTM800 User Manual

9.1 - 10

Warping Failure Troubleshooting

Failure:
PATS parameters WARP_RANGE, WARP_RES, FREQ_ERR or
WARP_SP failed
Connect the radio's accessory connector to the Tetra Com interface.
Connect the radio's antenna connector to the high power RF output
on the IFR.
Connect the 50 ohms RF probe to the low power RF input on the IFR.
Setup IFR:
Select high power input for measuring power at the antenna connector.
Select low power input for measuring with 50ohms RF probe.
No System,
TX Test,
TX Frequency 469.925MHz
Spectrum Analyser
Set Reference Level to 30dBm.
Run Tetra Com script for TX FGU Test.
Measure RF levels and frequencies with the 50ohms RF probe.
Measure DC levels with a multimeter.
If the cover is removed from the chassis, the RF PA is disabled to
prevent overheating of the FET devices. To measure the power at the
antenna connector, the pressure pad can be used to short the contact
area on the main board. This should be done only for a few seconds.
Start
RF
No
power at
TP5401 about
antenna connector
> 10dBm
?
Yes
No
Is frequency
FGU failure!
stable at 469.925MHz
Go to Main Synthesizer Chart.
+/-7kHz
?
Yes
Send Tetra Com
command "PN 0"
No
Is frequency
about 7kHz above
at Y5363 pin 1 about
469.925MHz
?
Yes
Yes
Check for 2.7V DC at
Send Tetra Com
Y5363 pin 4 before
command "PN 1FF"
replacing Y5363
No
Is frequency
about 7kHz below at Y5363 pin 1 about
469.925MHz
?
Yes Yes
OK
Replace Y5363
Tetra Com Script for TX FGU Test
TEST_ENTER
DELAY 18
Check for "Radio HW is READY"
MODE IDLE
INTR DIS
FREQ TX 469.925
L1TIMER ON
TX POW 4
RFTON ATT 0.5
RFTON FRQ 0
RFTON CHN I
FEEDBACK OPEN
MODE RFTONE
Use MODE IDLE to terminate transmit mode
Yes
No TX Output Power!
Go to RF Power Amplifier Chart.
RF
level at
-30 dBm
?
No
No JAVELIN Output Power!
Go to JAVELIN Chart.
No
DC
Replace U5331
2.4V
?
No
DC
Replace U5331
0.4V
?
TROUBLESHOOTING CHARTS: 450-470MHz