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    Replaced bad caps, still having problems

    I have a magnavox 32mf231d with a couple of caps that just failed, lucky me. The pair that were on the power supply board were 1200uf, 35v. I went to radio shack looking for the exact thing, and they did not have them. They did have 2200uf, 50v caps and I was told that these would be fine to use as because they held more capacity. I remove the broken caps, install the new caps and put everything back together. When I plug my screen in, there is a beeping/warning sound coming from the power supply board and the tv won't turn on. Any thoughts on what is now the problem? Is it that the caps are so far above the originals?

    #2
    Re: Replaced bad caps, still having problems

    most probably, you need low esr caps. some one will explain further.

    Comment


      #3
      Re: Replaced bad caps, still having problems

      You need low ESR caps [which rack-shack does not carry] and whoever told you 1200uF -> 2200uF was okay was a moron.

      Those caps are used to remove [filter] Ripple from the power supply.
      -
      The uF is chosen based on the expected Ripple frequency and the value of the inductor in the filter.
      Changing uF that far 'de-tunes' it from being optimized for that frequency.
      -
      GP caps [like places like rack-shack sell] have a higher ESR which [without getting too deep] means they have a higher resistance to Ripple and thus the Ripple tends to stay in the power circuits. IC chips don't work real well when voltage sent to them is jumping all over the place.
      .

      I hope you saved the old caps.
      Needed to get the ESR and Ripple specs to find correct replacements.
      .
      Mann-Made Global Warming.
      - We should be more concerned about the Intellectual Climate.

      -
      Be who you are and say what you feel, because those who mind don't matter and those who matter don't mind.

      - Dr Seuss
      -
      You can teach a man to fish and feed him for life, but if he can't handle sushi you must also teach him to cook.
      -

      Comment


        #4
        Re: Replaced bad caps, still having problems

        Radioshack has been worthless for most things since I was in High School.
        I Graduated in the 70's.
        .
        Mann-Made Global Warming.
        - We should be more concerned about the Intellectual Climate.

        -
        Be who you are and say what you feel, because those who mind don't matter and those who matter don't mind.

        - Dr Seuss
        -
        You can teach a man to fish and feed him for life, but if he can't handle sushi you must also teach him to cook.
        -

        Comment


          #5
          Re: Replaced bad caps, still having problems

          Pcbonez you have it backwards, he had 1200 if and ratshack sold him 2200uf caps.

          But everything else bonez said is right. Between the higher esr and higher capacity it probably detuned the circuit so bad it wont cycle properly. Post the brand and series of the caps and we can steer you in the right direction.

          Comment


            #6
            Re: Replaced bad caps, still having problems

            Essentially you need to keep in mind to maintain the capacitance rating and keep the same or higher voltage. Its always worth the extra 3 days to wait on a few ordered parts.

            Comment


              #7
              Re: Replaced bad caps, still having problems

              Originally posted by inuyasha.rules View Post
              Pcbonez you have it backwards, he had 1200 if and ratshack sold him 2200uf caps.

              But everything else bonez said is right. Between the higher esr and higher capacity it probably detuned the circuit so bad it wont cycle properly. Post the brand and series of the caps and we can steer you in the right direction.
              Thanks to you and bonez.

              The caps I had before were from CapXon. 1200uf, 35v.

              Are these from MCM going to fit the bill?

              http://www.mcmelectronics.com/produc...LAID=220394416

              Comment


                #8
                Re: Replaced bad caps, still having problems

                Dont know if this helps any but here are a couple of threads with this set.

                https://www.badcaps.net/forum/showthread.php?t=13566

                https://www.badcaps.net/forum/showthread.php?t=13832

                After your experience with that Radio Shak, I want to drive up there and fire the guy myself. I dont work for them but I'll tell the guy to punch out and go home!

                These (badcaps) guys are correct in telling you about this error.
                The strong-minded rise to the challenge of their goals,the weak-minded BECOME HATERS

                Comment


                  #9
                  Re: Replaced bad caps, still having problems

                  Originally posted by flavious27 View Post
                  The caps I had before were from CapXon. 1200uf, 35v.

                  Are these from MCM going to fit the bill?

                  http://www.mcmelectronics.com/produc...LAID=220394416
                  Wow, $3.83 for one no-name cap.

                  Digikey has Panasonic FC for $1.25 or Panasonic FR for 1.18. Shipping from digikey is around $2.50 USD and arrives in 48 hours.

                  The choice between FC an FR will depend on what original Capxon series you have. On the Capxon cap should be a two letter code as per this post

                  https://www.badcaps.net/forum/showpo...39&postcount=2
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                  Comment


                    #10
                    Re: Replaced bad caps, still having problems

                    Originally posted by inuyasha.rules View Post
                    Pcbonez you have it backwards, he had 1200 if and ratshack sold him 2200uf caps.

                    But everything else bonez said is right. Between the higher esr and higher capacity it probably detuned the circuit so bad it wont cycle properly. Post the brand and series of the caps and we can steer you in the right direction.
                    Which way is the arrow Hot Shot?
                    ""1200uF -> 2200uF""
                    I didn't get anything backwards.
                    .
                    Mann-Made Global Warming.
                    - We should be more concerned about the Intellectual Climate.

                    -
                    Be who you are and say what you feel, because those who mind don't matter and those who matter don't mind.

                    - Dr Seuss
                    -
                    You can teach a man to fish and feed him for life, but if he can't handle sushi you must also teach him to cook.
                    -

                    Comment


                      #11
                      Re: Replaced bad caps, still having problems

                      Originally posted by retiredcaps View Post
                      Wow, $3.83 for one no-name cap.

                      Digikey has Panasonic FC for $1.25 or Panasonic FR for 1.18. Shipping from digikey is around $2.50 USD and arrives in 48 hours.

                      The choice between FC an FR will depend on what original Capxon series you have. On the Capxon cap should be a two letter code as per this post

                      https://www.badcaps.net/forum/showpo...39&postcount=2
                      The other side says LZ 105 C then p608 vent

                      Comment


                        #12
                        Re: Replaced bad caps, still having problems

                        Here is the datasheet.


                        Ripple is obvious.
                        The ESR is for all intents and purposes is Impedance. [At 100kHz which is what they show.]
                        .
                        You want caps with the same or more Ripple.
                        And, the same or less ESR.
                        .
                        If your exact cap isn't in there it is special order.
                        In that case use the specs for the closest one [by uF/volts] with the same size can.
                        .
                        Last edited by PCBONEZ; 06-12-2011, 07:04 PM.
                        Mann-Made Global Warming.
                        - We should be more concerned about the Intellectual Climate.

                        -
                        Be who you are and say what you feel, because those who mind don't matter and those who matter don't mind.

                        - Dr Seuss
                        -
                        You can teach a man to fish and feed him for life, but if he can't handle sushi you must also teach him to cook.
                        -

                        Comment


                          #13
                          Re: Replaced bad caps, still having problems

                          Originally posted by PCBONEZ View Post
                          Here is the datasheet.


                          Ripple is obvious.
                          The ESR is for all intents and purposes is Impedance. [At 100kHz which is what they show.]
                          .
                          You want caps with the same or more Ripple.
                          And, the same or less ESR.
                          .
                          If your exact cap isn't in there it is special order.
                          In that case use the specs for the closest one [by uF/volts] with the same size can.
                          .
                          ooookay

                          So would something like this be okay:

                          http://search.digikey.com/scripts/Dk...name=P12406-ND

                          Comment


                            #14
                            Re: Replaced bad caps, still having problems

                            What size is the can on the old ones?
                            .
                            Mann-Made Global Warming.
                            - We should be more concerned about the Intellectual Climate.

                            -
                            Be who you are and say what you feel, because those who mind don't matter and those who matter don't mind.

                            - Dr Seuss
                            -
                            You can teach a man to fish and feed him for life, but if he can't handle sushi you must also teach him to cook.
                            -

                            Comment


                              #15
                              Re: Replaced bad caps, still having problems

                              Originally posted by PCBONEZ View Post
                              What size is the can on the old ones?
                              .
                              like 30mm tall, just a bit skinnier than a stick of chap stick.

                              Comment


                                #16
                                Re: Replaced bad caps, still having problems

                                Well, if I had a stick of chap stick....

                                The diameter is important.
                                .
                                Mann-Made Global Warming.
                                - We should be more concerned about the Intellectual Climate.

                                -
                                Be who you are and say what you feel, because those who mind don't matter and those who matter don't mind.

                                - Dr Seuss
                                -
                                You can teach a man to fish and feed him for life, but if he can't handle sushi you must also teach him to cook.
                                -

                                Comment


                                  #17
                                  Re: Replaced bad caps, still having problems

                                  Originally posted by PCBONEZ View Post
                                  Well, if I had a stick of chap stick....

                                  The diameter is important.
                                  .
                                  okay, say about 15 mm

                                  Comment


                                    #18
                                    Re: Replaced bad caps, still having problems

                                    That's way off.
                                    Let me know when you get a ruler or a tape measure.
                                    .
                                    Mann-Made Global Warming.
                                    - We should be more concerned about the Intellectual Climate.

                                    -
                                    Be who you are and say what you feel, because those who mind don't matter and those who matter don't mind.

                                    - Dr Seuss
                                    -
                                    You can teach a man to fish and feed him for life, but if he can't handle sushi you must also teach him to cook.
                                    -

                                    Comment


                                      #19
                                      Re: Replaced bad caps, still having problems

                                      Originally posted by PCBONEZ View Post
                                      That's way off.
                                      Let me know when you get a ruler or a tape measure.
                                      .
                                      at this hour? it looks like it is about 11mm, about the width of a microsd card.

                                      Comment


                                        #20
                                        Re: Replaced bad caps, still having problems

                                        Let me know when you get a ruler or a tape measure.
                                        Mann-Made Global Warming.
                                        - We should be more concerned about the Intellectual Climate.

                                        -
                                        Be who you are and say what you feel, because those who mind don't matter and those who matter don't mind.

                                        - Dr Seuss
                                        -
                                        You can teach a man to fish and feed him for life, but if he can't handle sushi you must also teach him to cook.
                                        -

                                        Comment

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