Onkyo SKW-540 hot transformer and amp

Collapse
X
 
  • Time
  • Show
Clear All
new posts
  • tibimakai
    Badcaps Legend
    • Jan 2012
    • 3680
    • USA

    #21
    Re: Onkyo SKW-540 hot transformer and amp

    I guess, I have celebrated to soon.
    By next day, it was hot again.

    Comment

    • budm
      Badcaps Legend
      • Feb 2010
      • 40746
      • USA

      #22
      Re: Onkyo SKW-540 hot transformer and amp

      Did you check the AC primary current draw with and without the secondary side connected to the load?
      Never stop learning
      Basic LCD TV and Monitor troubleshooting guides.
      http://www.badcaps.net/forum/showthr...956#post305956

      Voltage Regulator (LDO) testing:
      http://www.badcaps.net/forum/showthr...999#post300999

      Inverter testing using old CFL:
      http://www.badcaps.net/forum/showthr...er+testing+cfl

      Tear down pictures : Hit the ">" Show Albums and stories" on the left side
      http://s807.photobucket.com/user/budm/library/

      TV Factory reset codes listing:
      http://www.badcaps.net/forum/showthread.php?t=24809

      Comment

      • tibimakai
        Badcaps Legend
        • Jan 2012
        • 3680
        • USA

        #23
        Re: Onkyo SKW-540 hot transformer and amp

        0.175A.
        Though, I have to recognize how a stupid thing I did, I have installed the transformer inside the subwoofer and I wasn't sure, to which connector I have to connect the primary connector. Both connectors looked the same, with three pins. I was lazy to remove it again. I had to pull out the schematics to find which one is the right one.
        Later on I have noticed, that one has two wires and the other three(secondary +/ grd/ -).
        So, I have connected like that(reversed) and everything got quite hot. But after fixing my stupid thing, the sub still works, it is just to hot in my opinion(~49 Celsius).
        The output is 2x42V(84V total) and I have connected 120V at the same spot.
        The two main capacitors are 71V each.
        I have another SKW-540, with the same setup(dual sub setup in the living room), which I have just realized, that is not outputting any sound, but it turns on when it should(LED switches from red to green). This one, is a bit different internally then the other.
        I was thinking to swap boards/transformers between them, but it seems like I can't do that.
        Last edited by tibimakai; 11-12-2016, 06:03 PM.

        Comment

        • tibimakai
          Badcaps Legend
          • Jan 2012
          • 3680
          • USA

          #24
          Re: Onkyo SKW-540 hot transformer and amp

          Now, I'm measuring the original transformer and I'm not getting anything like before. It is 0.192 A now.
          Maybe, as it gets hotter the current draw starts increasing?

          Comment

          • tibimakai
            Badcaps Legend
            • Jan 2012
            • 3680
            • USA

            #25
            Re: Onkyo SKW-540 hot transformer and amp

            The second sub, started working again as soon as a I have removed that white paste(like Samsung used to use), from the final transistor's legs and heatsink.
            The board has a lot of this paste between the PCB and the backplate.
            Some of the parts, are completely embedded in it.

            Comment

            • budm
              Badcaps Legend
              • Feb 2010
              • 40746
              • USA

              #26
              Re: Onkyo SKW-540 hot transformer and amp

              AC Amp in primary without anything attached to the secondary winding is 0.175A
              @120vac is about 21VA. How much is it with the secondary side connected to the circuit?
              Never stop learning
              Basic LCD TV and Monitor troubleshooting guides.
              http://www.badcaps.net/forum/showthr...956#post305956

              Voltage Regulator (LDO) testing:
              http://www.badcaps.net/forum/showthr...999#post300999

              Inverter testing using old CFL:
              http://www.badcaps.net/forum/showthr...er+testing+cfl

              Tear down pictures : Hit the ">" Show Albums and stories" on the left side
              http://s807.photobucket.com/user/budm/library/

              TV Factory reset codes listing:
              http://www.badcaps.net/forum/showthread.php?t=24809

              Comment

              • tibimakai
                Badcaps Legend
                • Jan 2012
                • 3680
                • USA

                #27
                Re: Onkyo SKW-540 hot transformer and amp

                Soon I will measure that as well, but I believe that this is how is should be.
                The other one one has more electronics including a relay. That one, is just slightly warm.

                Comment

                • tibimakai
                  Badcaps Legend
                  • Jan 2012
                  • 3680
                  • USA

                  #28
                  Re: Onkyo SKW-540 hot transformer and amp

                  So, with everything hooked up(except LED) I measure 0.223 A.

                  Comment

                  Related Topics

                  Collapse

                  • nobbnobb1
                    Transformer Whine: Can it be rebuilt? Mirage S8 Subwoofer
                    by nobbnobb1
                    Hi guys,

                    I'm trying to repair my Mirage S8 subwoofer (equivalent to the Energy S8.3) which is an excellent unit. It developed a light hum recently, which I thought was the capacitors. I replaced all the capacitors, and upon reassembly the buzz got louder. I thought I had messed something up electronically, but even when I swapped out the old capacitors it was still buzzing. So I inspected closer and discovered the noise is coming from the transformer. It's REALLY loud, which was surprising.

                    There are no specs on the transformer and no relevant part numbers. I Googled...
                    09-20-2022, 09:54 PM
                  • ohren
                    Original Xbox 1.0 PSU: Foxlink FTPS-0002 Rev. B. — 12 V low, 5 V high — transformer?
                    by ohren
                    Hello!

                    I'm looking at an original Xbox PSU: Foxlink ftps-0002 rev. B. The 12 V output is too low, and the 5 V output is too (?) high. Unfortunately I don't have an oscilloscope but only a DMM for diagnosis.

                    Measured voltages with no load:

                    After rectifier diodes
                    12V: 6.17 V
                    5V: 5.67 V

                    Secondary transformer pins AC measurement (really don't know if this says anything)
                    12V: 2-2.5 V
                    5V: 1.04 V


                    I also have another (working) Xbox psu from Delta. The same measures there, in order, being: 10.79,...
                    03-18-2023, 10:33 AM
                  • rustinjust
                    Please help, subwoofer connected to tv, read description below
                    by rustinjust
                    I've got a subwoofer that I've had for nearly 20 years, it did come with a basic remote which I've lost. It's a generic make of subwoofer, I can't see a brand sticker on it. It comes with 2 speakers.

                    Question recently I've connected it up to my tv which has greatly improved the sound on my tv, however I'd like to be able to mute the subwoofer when ads come on or just mute it when the phone rings etc. I tried using a cheap all in one tv remote on the subwoofer and the volume button would only work to increase volume but not turn it down or mute it

                    Is there a way of...
                    10-28-2023, 07:09 AM
                  • rustinjust
                    Please help, where can I get a remote for my subwoofer?
                    by rustinjust
                    I’ve got a subwoofer that I’ve had for nearly 20 years, it did come with a basic remote which I’ve lost. It’s a generic make of subwoofer, I can’t see a brand sticker on it. It comes with 2 speakers.

                    Question recently I’ve connected it up to my tv which has greatly improved the sound on my tv, however I’d like to be able to mute the subwoofer when ads come on or just mute it when the phone rings etc. I tried using a cheap all in one tv remote on the subwoofer and the volume button would only work to increase volume but not turn it down or mute it

                    Is there...
                    10-28-2023, 03:43 AM
                  • mikey5791
                    Is it possible for transformer substitution?
                    by mikey5791
                    Hi all,
                    Got this local made DC power supply (12/14V) given free as the transformer has melted. There is no marking or indication to identify what type or rating of transformer used.
                    Fyi,. I had a busted autogate mainboard with transformer with marking 13-0-13 . Is this the 13v dc type transformer?
                    My questions are
                    1. How do i test to see if the transformer is in good working condition?
                    2. Can this transformer (marking 13-0-13) be used to replace the melted transformer on the DC power supply?
                    Hope you guys understand what i was asking. My intention is...
                    11-03-2022, 02:11 AM
                  • Loading...
                  • No more items.
                  Working...