Wednesday, April 24, 2013

MITSUBISHI CRT PTV - VS-50111 / VS-60111 / WS-48311 / WS-55311 / WS-55411 / WS-65311 / WS-65411 / WS-73411 -HOW TO REPLACE CRT - HOW TO DETACH ANODE LEAD



CRT REPLACEMENT
High voltage should be completely discharged prior to CRT removal.  Since The CRTs receive high voltage from the CR Block, discharge by shorting the open end of the respective high voltage cable to chassis ground.
  • Remove the Speaker Grille, Front Board, and Screen Assy.
  • Remove the Back Board.
  • Remove the Anode Lead Wire from the CR Block.
  • Remove the PCB-CRT.
  • Remove 4 hex-screws "a" retaining the Optical Unit.
  • Remove 4 screws "b" retaining the Lens.
Note: DO NOT loosen the RED screws. Doing so will break the seal between the C-Element and the # 6 Lens, causing leakage of the CRT Coolant.
  • Remove 4 screws "c" retaining the CRT.
  • Remove the Deflection Yoke from the neck of the CRT.
Note: The 4 spring-loaded screws and labeled as "DO NOT REMOVE", should not be loosened under any circumstance. Doing so will break the seal between the CRT and the CRT-Spacer, causing leakage of the CRT Coolant.
INSTALLATION OF CRT
The replacement CRT is supplied as an assembly comprised of the CRT and the Inner Lens with the space between them filled with ethylene glycol. Care should be taken during handling and installation to prevent shock from disrupting the seal or alignment between the CRT and Inner Lens.
Note: The CRT fixing screws should not be loosened nor should they be removed.
Carefully position the replacement CRT and fasten in place using 4 screws "d".

  • Install the Deflection Yoke on the CRT neck.
  • Install the Lens that was removed in steps 5 and 6 of Removal Of The CRT.
  • Position the Lens so that the Label faces the direction shown.
  • Install the mounting screws.
  • Install the PCB-CRT.
  • Insert the Optical Unit into the Light Box Assembly.
  • Insert the Anode Lead Wire into the Flyback Transformer.
  • Re-clamp the Lead Wire in its original position.

Adjustment procedures after replacing the CRT(s)
  1. CRT Cut Off / White Balance Adjustment
  2. Static Convergence Adjustment
  3. Dynamic Convergence Adjustment.
ANODE LEAD REMOVAL
To prevent damage, the following procedure must be used when removing an Anode Lead from the Flyback Transformer.