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Another LCT2662 with badcaps

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    Another LCT2662 with badcaps

    First , my name is Chris and new to thhis site. Hope i'm putting these in the right place if not, i'm sure i'll hear about.

    I was given a LCT2662 that quit working. I came from an investment bank/stock exchange were it was set to the stock exchange. My guess it was on 24/7/365 as the remote still had original batteries with almost full charge.
    Looked here before deciding to keep it or trash it. After looking at the three PCB's (pcb#1 tuner, pcb#2 audio/main, and pcb#3 PSU) I decided to recap it to see if it will work, and yes I play the lottery hoping to win BIG! LOL!

    Question #1
    What's the best place to order caps that are all the same brand, and what is the best brand? I plan to replace all radial caps with high temperature caps, all 110. The hardest ones to locate are two 100uF 450V, slim pickens.

    Question #2
    Does anyone have the service manual for this tv? The one I got from here has a totally different schematic and bill of material. I have included photos.

    Question #3
    In photo #2, there is a component I believe to be a crystal/oscillator that was leaking like a cap. It's mark as H27.000M and is located at Y1, below the heat sink in the middle and to the right of the three clustered caps. I need it's specs to order a new one. If it leaked, replace! Photo #4 is a closeup of said component.

    Question #4
    What to use to clean up cap puke from the PCB's?

    Any and all advice and help would be appreciated.

    P.S. I tried to attach the four photos, but they're too large to upload. E-mail me at cmj21973@yahoo.com and I'll send them to you.
    Last edited by cmj21973; 03-02-2010, 10:46 PM.

    #2
    Re: Another LCT2662 with badcaps

    Here's the photos thatgo with my original post.
    Attached Files

    Comment


      #3
      Re: Another LCT2662 with badcaps

      Originally posted by cmj21973
      First , my name is Chris and new to thhis site.
      (Everyone) Hi, Chris.
      Originally posted by cmj21973
      Hope i'm putting these in the right place if not, i'm sure i'll hear about.
      You did, and you would have.
      Originally posted by cmj21973
      I was given a LCT2662 that quit working. I came from an investment bank/stock exchange were it was set to the stock exchange. My guess it was on 24/7/365 as the remote still had original batteries with almost full charge.
      Looked here before deciding to keep it or trash it. After looking at the three PCB's (pcb#1 tuner, pcb#2 audio/main, and pcb#3 PSU) I decided to recap it to see if it will work, and yes I play the lottery hoping to win BIG! LOL!

      Question #1
      What's the best place to order caps that are all the same brand, and what is the best brand? I plan to replace all radial caps with high temperature caps, all 110. The hardest ones to locate are two 100uF 450V, slim pickens.
      I prefer to use Panasonic FM or FC series caps from Digikey (www.digikey.com). Other brands are also good; you can fine a list of preferred brands and series in the "Which Caps Should I Buy" thread in the FAQ. Don't get hung up on using the same brand for all of them.
      Originally posted by cmj21973
      Question #2
      Does anyone have the service manual for this tv? The one I got from here has a totally different schematic and bill of material. I have included photos.
      Search, and search again. Searching for 'schematic' tends to produce better results, but it's still hit or miss getting what you need.
      Originally posted by cmj21973
      Question #3
      In photo #2, there is a component I believe to be a crystal/oscillator that was leaking like a cap. It's mark as H27.000M and is located at Y1, below the heat sink in the middle and to the right of the three clustered caps. I need it's specs to order a new one. If it leaked, replace! Photo #4 is a closeup of said component.
      That IS a crystal. They don't leak.
      Originally posted by cmj21973
      Question #4
      What to use to clean up cap puke from the PCB's?
      I don't see any evidence of leakage, perhaps a better closeup would help.
      Originally posted by cmj21973
      Any and all advice and help would be appreciated.
      Buy low. Sell high.

      Don't publish your email address in an open forum.

      Wash your hands before you eat.

      Flush.

      Warm cookies and cold milk are good for you.

      When in doubt, ask.

      PlainBill
      For a number of reasons, both health and personal, I will no longer be active on this board. Any PMs asking for assistance will be ignored.

      Never be afraid to try something new. Remember, amateurs built the ark. Professionals built the Titanic.

      Comment


        #4
        Re: Another LCT2662 with badcaps

        Thanks PlainBill.
        I removed whatever it was around the crystal, to see the Y1 print on the PCB, before I took the photo.

        I'll order my caps and post an update after I recap it.

        Comment


          #5
          Re: Another LCT2662 with badcaps

          Originally posted by cmj21973
          Thanks PlainBill.
          I removed whatever it was around the crystal, to see the Y1 print on the PCB, before I took the photo.

          I'll order my caps and post an update after I recap it.
          A couple of other points: The power supply appears to have a Power Factor Correction front end. If I am correct, the two 100uF, 450V caps must be low ESR per Wizard.

          When selecting caps, make sure you have sufficient room for the replacements. From personal experience, a cap of a specific size / voltage can be available in three different physical sizes (regular, short, and long). It's frustrating to have ordered the regular when you needed the short.

          PlainBill
          For a number of reasons, both health and personal, I will no longer be active on this board. Any PMs asking for assistance will be ignored.

          Never be afraid to try something new. Remember, amateurs built the ark. Professionals built the Titanic.

          Comment


            #6
            Re: Another LCT2662 with badcaps

            Your correct. That's why I mention them being a problem. There are two Al plates I had to remove to access the caps. I have located replacements, EKMQ451VN101MQ25S by UCC ( United Chemi-Con). They're the only two caps that are not Panasonic.

            Another question, has long as the replacement cap's capacitance is the same it's voltage can be higher correct?

            Thanks

            Comment


              #7
              Re: Another LCT2662 with badcaps

              Originally posted by cmj21973
              Your correct. That's why I mention them being a problem. There are two Al plates I had to remove to access the caps. I have located replacements, EKMQ451VN101MQ25S by UCC ( United Chemi-Con). They're the only two caps that are not Panasonic.

              Another question, has long as the replacement cap's capacitance is the same it's voltage can be higher correct?

              Thanks
              Yes, with a warning. A cap with a higher voltage rating may be in a larger package, so make sure it will fit.

              PlainBill
              For a number of reasons, both health and personal, I will no longer be active on this board. Any PMs asking for assistance will be ignored.

              Never be afraid to try something new. Remember, amateurs built the ark. Professionals built the Titanic.

              Comment


                #8
                Re: Another LCT2662 with badcaps

                I've been side tracked but back on track.

                I'm replacing all caps with Panasonic FC series A type except for two 100uF-450V caps, they're Panasonic HC series TS type. Had to change part supplier. First choice's back order was into late August, final choice's is into middle of May.

                Found a cheap source of thermal compound .798 oz for $4.22 tax included.

                I'll place my order in a couple of days to allow for any replies. Meanwhile, workbench is prepped and waiting.

                Comment


                  #9
                  Re: Another LCT2662 with badcaps

                  Omg, I just fixed one of those myself. For a cheap lil' TV, they're not tooooo terrible. Just don't plan on using it with any reasonable VGA resolutions, unless you like the words "Main Not Support!!" I used a mix of EPCOS and United Chemicon caps on mine, and despite being the brutally wrong caps, it's held up for about 5 months now.

                  Comment


                    #10
                    Re: Another LCT2662 with badcaps

                    UPDATE

                    My caps came in and I double checked that they're the right values and quantities. Decapped all three boards with 45watt desoldering iron from the Shack. I'll recap the tuner (pic 1) and main (pic 2) boards tomorrow. As for the power (pic 3 & 4) board, I need fix the area damaged by the leaking electrolytic.
                    I'm think of using Dullcote Lacquer, to cover the exposed copper, before recapping it. I'll try it on a pratice board first.
                    Attached Files

                    Comment


                      #11
                      Re: Another LCT2662 with badcaps

                      let's just hope you took notes which caps went where before desoldering all of them

                      Comment


                        #12
                        Re: Another LCT2662 with badcaps

                        I took notes and photos. I also printed B&W 8.5 x 11 of each board, and used double stick photo tape to attach each cap.
                        Can't recall offhand what its called, but I reffer to them as a "Build Board".
                        Attached Files

                        Comment


                          #13
                          Re: Another LCT2662 with badcaps

                          UPDATE

                          I used the Dullcote lacquer to repair the PSU, and recapped all three boards. Checked solder joints, removed flux residue with hot water,Dawn dishsoap, and toothbrush. Rinsed with water and aired dried, in front of fan, overnight. Rinsed again with 91% alcohol.
                          Applied thermal compound, from local auto parts store, and reinstall AL plates on the PSU.
                          Installed PSU only and powered up, no smoke and no BANG! Only noise is a buzzing sound while on standby. Install MAIN board , only connecting to the PSU, and powered up, no smoke and no BANG! Still buzzing sound. Installed TUNER board, only connecting to the PSU, and powered up, no smoke and no BANG! Still buzzing sound.
                          I reconnect the rest of cables and reassemble the tv set. I connected a tv cable, A/V input source, and turn on the set. Still a buzzing sound while in standby mode, may be normal I don't known, but the buzzing sound does go away when out of standby, ie when watching tv.
                          For $58.16, I now have a working AKAI LCT2662N 26" Wide-Screen LCD TV

                          Thanks again PlainBill for your help and input.
                          Attached Files

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