Technika LCD42-910 Buzzing PSU

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  • Wabby
    Member
    • Apr 2014
    • 30
    • UK
    #1

    Technika LCD42-910 Buzzing PSU

    Hi Guys,

    Recently stripped down a LCD42-910 that is making a buzzing noise.
    Straight away saw 3/4 caps that were bulging - One with a hole! Result, or so I thought.

    Swapped them out, and still have the noise.

    Anybody any ideas?

    Im assuming its to do with those diodes up the top, but have no idea how to test them, and they show values in BOTH directions :S
    Attached Files
    Last edited by Wabby; 07-06-2015, 02:13 PM.
    Tags: None
    • sordids999
      Badcaps Legend
      • May 2013
      • 2152
      • uk
      #2
      Re: Technika LCD42-910 Buzzing PSU

      Take one leg of the diode out of circuit and measure again,and im thinking the buzzing noise is coming from the picture i have uploaded ?
      Attached Files
      Last edited by sordids999; 07-06-2015, 02:39 PM.

        Comment

        • Wabby
          Member
          • Apr 2014
          • 30
          • UK
          #3
          Re: Technika LCD42-910 Buzzing PSU

          Yes from that area. Any ideas?

          I will pull the diodes out and test.

            Comment

            • Wabby
              Member
              • Apr 2014
              • 30
              • UK
              #4
              Re: Technika LCD42-910 Buzzing PSU

              Top left circled area ish. Could also be coming from the 3 components under the heatsink in the middle at top

                Comment

                • Wabby
                  Member
                  • Apr 2014
                  • 30
                  • UK
                  #5
                  Re: Technika LCD42-910 Buzzing PSU

                  Anybody else any bright ideas?

                  TV works perfect, just this very faint humming noise gets annoying when you 'hear' it because once you have heard it, you cannot unheard it. lol

                    Comment

                    • Wabby
                      Member
                      • Apr 2014
                      • 30
                      • UK
                      #6
                      Re: Technika LCD42-910 Buzzing PSU

                      Checked and everything seems fine - Shame about the buzzing still though

                        Comment

                        • ReeceyBurger123
                          Never Give Up !
                          • May 2014
                          • 7325
                          • Britain
                          #7
                          Re: Technika LCD42-910 Buzzing PSU

                          These power supplies do hum because of the poor feed back and oscillation trust me you think thats bad wait till you hear a 17pw25-4 that sounds like a fucking car on a bad day they are the worst, its probably fine yes it might hum but just take your mind off it and dont obsess over it thats when you will notice it. My plasma buzzes and I used to obsess over it but just ignore it recap it fully with good caps for safety you never said but does the set work ?
                          Please Do Not PM My Page Asking For Help Badcaps Is The Place For Advise, Page Linked For Business Reasons Only. Anyone Doing So Will Be Banned Instantly !

                          https://www.facebook.com/Telford-Tel...7894576335359/

                            Comment

                            • stj
                              Great Sage 齊天大聖
                              • Dec 2009
                              • 31028
                              • Albion
                              #8
                              Re: Technika LCD42-910 Buzzing PSU

                              wax or epoxy covering the coils may help.

                                Comment

                                • Wabby
                                  Member
                                  • Apr 2014
                                  • 30
                                  • UK
                                  #9
                                  Re: Technika LCD42-910 Buzzing PSU

                                  Yeah set works fine.

                                  Will epoxy damage anything?

                                    Comment

                                    • ReeceyBurger123
                                      Never Give Up !
                                      • May 2014
                                      • 7325
                                      • Britain
                                      #10
                                      Re: Technika LCD42-910 Buzzing PSU

                                      Epoxy will be fine on the transformers will just muff out the buzzing noise as they normally are the cause.
                                      Please Do Not PM My Page Asking For Help Badcaps Is The Place For Advise, Page Linked For Business Reasons Only. Anyone Doing So Will Be Banned Instantly !

                                      https://www.facebook.com/Telford-Tel...7894576335359/

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