Reports of a PLL unlock on the lower frequencies may be due to low VCO levels. The following change will increase the VCO level and should prevent reoccurrence of this symptom.
Parts required
C168, change to 15 pF 50V (CC45SLIH150J)
Procedure:
- On the RF unit (X44-1660-00) change C168 from a 33 pF capacitor to a 15 pF 50V capacitor.
- Readjust the VCO BPF (RF unit L74-76) according to the instructions contained in the TS-940 Service manual.
This change is applicable to units prior to serial number 606xxxx.
Time required for this modification is 1 hour or less.
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