Trying to repair a SONY PVM 9042QM

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    • Trying to repair a SONY PVM 9042QM

      Hello !

      i bought in october 2019, 2 9“ sony 9042QM PVM.
      One was always black and white. I managed to solve the problem after a deep cleaning and some soldering reflow here and there where the solders were looking suspicious.

      the other one has a screwed image on the left and right side with some king of wiggling on the sides.
      The wiggling is more and more visible if i turn brightness all the way up. And tends to disappear but not completely, when the brightness is very low.

      please take a look at the picture.

      what i tried so far.

      i swapped the B board and the D board from the working unit to the non working one.
      nothing had changed.

      please refer to the attached link for the service manual…-Trinitron-Pvm-8042q.html

      as per the manual, D board deals with
      H oscillation freq, screen phase, H/V BLK, H/V deflection, H/V delay, while B bord deals with primary colors matrix, burst gate width, VXO, NTSC/PAL/SECAM, chroma pulse.

      When i swapped the boards, the working unit had still its beautiful Picture.

      now i start thinking that the P board which contains the EHT has a problem. Maybe the EHT itself ?

      do you guys can give me a path to follow ?
      Can i swap P board to test ? Isn’t it dangerous for the tube ?
      What should i do next ?

      i didn’t touch any Of the potentiometers.

      thanks for any comment or any help.

      ...I make things with my hands...