Tait TM8100 mobiles Service Manual page 200

Figure 9.7 Components between the digital board and the frequency synthesizer
Task 8 —
Reference
Frequency
200 Frequency Synthesizer Fault Finding
FCL TOP CAN
If the supply for the charge pump is correct, check the reference frequency
input from the FCL to the PLL.
1. Measure the reference frequency at pin 8 of IC503 (see
pin 8 of IC503: 13.012 ± 0.002 MHz and 1.1 ± 0.2V
A4 band: pin 8 of IC503: 2.612 ± 0.002 MHz and 1.1 ± 0.2V
2. If the signal is correct, go to
3. Check IC503 (see
4. Determine if the fault has been removed. If it has, go to
on page 163. If it has not, the FCL is suspect; go to
for FCL" on page
Task 9. If it is not, go to
Figure 9.2). Replace IC503 if it is suspect.
234.
© Tait Electronics Limited November 2007
VIAS FOR
MEASUREMENTS
Figure 9.2).
pp
pp
Step 3.
"Final Tasks"
"Power Supply
TM8100/TM8200 Service Manual