Panasonic PT- 47WX49E Service Manual

Also see for PT- 47WX49E: Schematic Notes

Contents

- 3 - Service ManualImportant Safety TestsMeasuring H.V.The anode caps are cemented to the CRTs. To gainaccess for high voltage measurement, remove the redCRT’s anode lead from the flyback transformerdistributor. Grasp the anode lead protective cap at itsbottom and squeeze it against the locking cap bodyinside, Rotate 1/4 turn counter clockwise and pull theanode lead sleeve out of the FBT distributor. Connect ahigh voltage lead (+) from your H.V. meter to the FBTdistributor, and the common (-) to cold ground ( ).(See Fig. 2).Note: Reinsert the anode lead into the FBTdistributor until it is tightly and fully seated.Turn the locking cap clockwise to lock in place.(EHT) Protector Operation CheckWith the cabinet back removed, apply a nominal 120VAC to the PTV.Over Voltage TestPreparation:1. Turn PTV “OFF”2. Connect an NTSC signal generator to theantenna terminal.3. Connect DVM (+) TPD50 and (-) TPD51 onD Board. (See Fig. 4)Figure 3. Measuring H.V.4. Connect a H.V. meter (static type, class 0.1) withhigh voltage leads to high voltage distributoron FBT. (See Fig. 4)Figure 4. DVM & Power supply connection.Connect the 15 ~ 25 V DC variable power supply to (+)TPD8 or IC802 pin 2 (D-Board) and (-) heat sink ofQ551 (See Fig. 4).Procedures:1. Apply a monoscope pattern.2. Turn PTV ON.3. Adjust the Picture or Brightness controls so that theDVM reads 12.4 volts ± 0.4 volts.4. Increase the variable power supply until set turnsoff. The set should turn off at 12.4 volts ± 0.4 volts(DVM) and high voltage less than 36.4kV.5. If the DVM reading is other than 12.4 volts (± 0.4volts), readjust picture or brightness control andrepeat steps 3.6. Turn off the variable supply and confirm that the setwill turn on with the Remote Control.Figure 2. Removal of FBT leadsFBT DistributorAnode leadGrasp protectiverubber capPush & rotatecap counter-clockwiseto removeDischarge toCRT Chassis312-+H.V. METERFBT DistributorCRTCHASSISCold Ground-+DVMTPD51 TPD50 D-BoardVariablePowerSupply(15~25DC)(+)(-)IC802 PIN 2HEAT SINK OF Q551MA150 D-Board100Ω 1/2 WOR TPD8