Tait TM9100 - Page 210

210 Frequency Synthesizer Fault Finding TM9100 Service Manual
© Tait Electronics Limited August 2005
Task 29 —
Repair PLL feedback
If both the maximum and minimum VCO frequencies are correct, then the
PLL feedback is suspect.
1. Resolder R542 in position (see Figure 9.12).
2. Remove the
VCO BOT can.
3. Replace the components L510 (see Figure 9.13) and IC503
(see Figure 9.12).
4. Confirm that the fault in the radio has been removed. If it has, go to
“Final Tasks” on page 147. If it has not, replace the main-board
assembly and go to “Final Tasks” on page 147.
Figure 9.13 Synthesizer circuitry under the VCO BOT can (VHF radio, bottom side)
VCO BOT
1 2
3