Some users of the TS-930S have reported a problem where the PLL will sometimes not lock (digital display does not come on) if the power switch is turned off and on while xx.499.9 MHz is displayed, after the unit has warmed up. This may occur also in the FSK mode.
This may be caused by detuning of VCO-2 and VCO3 in the PLL unit (X50-1880-00). This may be cured by a simple increase in the voltage obtained in the PLL alignment procedure. Make the following change in your service manual.
Service Manual page 58.
3. VCO-3 T14 change 3.7v to read 4.2 vdc
4. VCO-2 T15 change 3.0v to read 3.5 vdc
Notes:
Be sure to adjust T14 and T15 of VCO-2 and VCO3 whenever a PLL
related circuit is serviced.
This change applies to units before S/N 306XXXX.
Installation time for this change is 1/2 hour or less.
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