Announcement

Collapse
No announcement yet.

MAGNAVOX no picture powers LED 47MF437B/37

Collapse
X
Collapse
 
  • Page of 7
  • Filter
  • Time
  • Show
Clear All
new posts
Previous 1 2 3 4 5 6 7 template Next
    #61
    Re: MAGNAVOX no picture powers LED 47MF437B/37

    Pulled the diodes Test Results Below.

    Diode 1 show 18 in both directions

    Diode 2 shows 779 Red probe on output side.
    455 Black probe on output side.

    Output side being the one with the stripe.

    Also some of the pad came up on the burned area when removing these Diodes.
    Can I use a paperclip or some wire to bridge the two together?

    And are there any stores that would carry these diodes?
    I browsed Radio Shack website and couldn't find the "P6KE120A" diodes.

    Thank You So Much For The Help!!!!!
    Attached Files

    Comment

      #62
      Re: MAGNAVOX no picture powers LED 47MF437B/37

      Originally posted by scatman0000 View Post
      Pulled the diodes Test Results Below.

      Diode 1 show 18 in both directions

      Diode 2 shows 779 Red probe on output side.
      455 Black probe on output side.
      Diode 1 is definitely bad. Diode 2 is probably bad with those readings. I would play it safe and replace both.

      Also some of the pad came up on the burned area when removing these Diodes.
      Can I use a paperclip or some wire to bridge the two together?
      Use an insulated wire. See

      http://www.circuitrework.com/guides/6-1.shtml

      And are there any stores that would carry these diodes?
      I browsed Radio Shack website and couldn't find the "P6KE120A" diodes.
      Get it from digikey. It costs around $2.75 USD for shipping and you get it in about 2 days. It is 60 cents at digikey. I would get 4 and have a couple of spares.

      http://search.digikey.com/us/en/prod...ACT-ND/2770358
      --- begin sig file ---

      If you are new to this forum, we can help a lot more if you please post clear focused pictures (max resolution 2000x2000 and 2MB) of your boards using the manage attachments button so they are hosted here. Information and picture clarity compositions should look like this post.

      We respectfully ask that you make some time and effort to read some of the guides available for basic troubleshooting. After you have read through them, then ask clarification questions or report your findings.

      Please do not post inline and offsite as they slow down the loading of pages.

      --- end sig file ---

      Comment

        #63
        Re: MAGNAVOX no picture powers LED 47MF437B/37

        Thank you for your help, Would a automotive wire 18 to 22 gauge work?
        They have insulation on them and I have plenty of that available to me.
        The website for the diodes looks like a decent site, I will order from there.
        Thanx Again

        Comment

          #64
          Re: MAGNAVOX no picture powers LED 47MF437B/37

          Originally posted by scatman0000 View Post
          Thank you for your help, Would a automotive wire 18 to 22 gauge work?
          I'm not a solder repair expert, but I believe it should work fine. Use your multimeter's continuity feature to "buzz" your work afterwards to ensure good electrical connection.

          The website for the diodes looks like a decent site, I will order from there.
          Many USA regulars here use digikey and I have never heard of a negative experince yet in 2 years of participation. For non USA members, expensive shipping costs force us to choose alternatives.
          --- begin sig file ---

          If you are new to this forum, we can help a lot more if you please post clear focused pictures (max resolution 2000x2000 and 2MB) of your boards using the manage attachments button so they are hosted here. Information and picture clarity compositions should look like this post.

          We respectfully ask that you make some time and effort to read some of the guides available for basic troubleshooting. After you have read through them, then ask clarification questions or report your findings.

          Please do not post inline and offsite as they slow down the loading of pages.

          --- end sig file ---

          Comment

            #65
            Re: MAGNAVOX no picture powers LED 47MF437B/37

            Thank you, Will wait until I get my diodes installed and then will report back.

            This Forum has so far proven to be very helpful.

            Thank you to every one who replied.

            Comment

              #66
              Re: MAGNAVOX no picture powers LED 47MF437B/37

              Hmm, I should have also asked you to check the two diodes just below the two ZD diodes. Check them the same way in circuit first and report your readings. These two diodes may be collateral damage victims?
              --- begin sig file ---

              If you are new to this forum, we can help a lot more if you please post clear focused pictures (max resolution 2000x2000 and 2MB) of your boards using the manage attachments button so they are hosted here. Information and picture clarity compositions should look like this post.

              We respectfully ask that you make some time and effort to read some of the guides available for basic troubleshooting. After you have read through them, then ask clarification questions or report your findings.

              Please do not post inline and offsite as they slow down the loading of pages.

              --- end sig file ---

              Comment

                #67
                Re: MAGNAVOX no picture powers LED 47MF437B/37

                He should still be able to add to his order. My experience with placing a digikey order over the weekend is they won't ship till monday evening. I usually get the ship email somewhere in the 9:30 pm eastern time.

                Comment

                  #68
                  Re: MAGNAVOX no picture powers LED 47MF437B/37

                  The Diode in location "D925" measured "555" in one direction only, Infinite in the other.

                  The Diode in location "D907" measured "572" in one direction only, Infinite in the other.

                  The Diode in location "D912" measured "001" in both directions. Should I pull this one too and test it out of the board?

                  Comment

                    #69
                    Re: MAGNAVOX no picture powers LED 47MF437B/37

                    Originally posted by scatman0000 View Post
                    The Diode in location "D912" measured "001" in both directions. Should I pull this one too and test it out of the board?
                    D912 is bad if it tests 001 both ways. Yes, desolder and retest out of circuit.
                    --- begin sig file ---

                    If you are new to this forum, we can help a lot more if you please post clear focused pictures (max resolution 2000x2000 and 2MB) of your boards using the manage attachments button so they are hosted here. Information and picture clarity compositions should look like this post.

                    We respectfully ask that you make some time and effort to read some of the guides available for basic troubleshooting. After you have read through them, then ask clarification questions or report your findings.

                    Please do not post inline and offsite as they slow down the loading of pages.

                    --- end sig file ---

                    Comment

                      #70
                      Re: MAGNAVOX no picture powers LED 47MF437B/37

                      Thank you, I will do that tomorrow. Also should I be worrying about my transformer or is that thing bullet proof?

                      Thanx Again!

                      Comment

                        #71
                        Re: MAGNAVOX no picture powers LED 47MF437B/37

                        Originally posted by scatman0000 View Post
                        Also should I be worrying about my transformer or is that thing bullet proof?
                        The big SMPS transformers rarely go bad. I see a Capxon cap by those fried diodes. They are terrible quality. If you can add to your order, I would replace all the Capxon caps with Panasonic FM equivalents.
                        --- begin sig file ---

                        If you are new to this forum, we can help a lot more if you please post clear focused pictures (max resolution 2000x2000 and 2MB) of your boards using the manage attachments button so they are hosted here. Information and picture clarity compositions should look like this post.

                        We respectfully ask that you make some time and effort to read some of the guides available for basic troubleshooting. After you have read through them, then ask clarification questions or report your findings.

                        Please do not post inline and offsite as they slow down the loading of pages.

                        --- end sig file ---

                        Comment

                          #72
                          Re: MAGNAVOX no picture powers LED 47MF437B/37

                          Originally posted by scatman0000 View Post
                          Hello, I am also a newbie to psu repair.
                          Just a reminder that when you install the new diodes, you must put them back in correct direction as the originals. A diode's job is to allow current flow in one direction.
                          --- begin sig file ---

                          If you are new to this forum, we can help a lot more if you please post clear focused pictures (max resolution 2000x2000 and 2MB) of your boards using the manage attachments button so they are hosted here. Information and picture clarity compositions should look like this post.

                          We respectfully ask that you make some time and effort to read some of the guides available for basic troubleshooting. After you have read through them, then ask clarification questions or report your findings.

                          Please do not post inline and offsite as they slow down the loading of pages.

                          --- end sig file ---

                          Comment

                            #73
                            Re: MAGNAVOX no picture powers LED 47MF437B/37

                            Use the 22 wire to brige the connection instead of the 18 guage, 18 is too thick, youll be soldering all day.
                            Fixed so far 12 lcd's , 1 plasmas, 5 monitors, 0 dlp's (plan to keep the dlps at 0). and 3 atx power supplies, and 2 motherboards.

                            Comment

                              #74
                              Re: MAGNAVOX no picture powers LED 47MF437B/37

                              Diode "D912" Test "584" in output side
                              Test "infinite" in other side.

                              That is taken out of the board.

                              Should I put that one back in?

                              Should I be worried about the test readings when it was in the board?

                              I will also look at getting the other capacitors. Might as well since I am doing all this.

                              Thank You !!

                              Comment

                                #75
                                Re: MAGNAVOX no picture powers LED 47MF437B/37

                                Originally posted by scatman0000 View Post
                                Diode "D912" Test "584" in output side
                                Test "infinite" in other side.

                                That is taken out of the board.
                                That is a good diode. If you haven't desoldered all the bad components, the in circuit reading that you were getting for D912 may have been affected by the bad components.
                                --- begin sig file ---

                                If you are new to this forum, we can help a lot more if you please post clear focused pictures (max resolution 2000x2000 and 2MB) of your boards using the manage attachments button so they are hosted here. Information and picture clarity compositions should look like this post.

                                We respectfully ask that you make some time and effort to read some of the guides available for basic troubleshooting. After you have read through them, then ask clarification questions or report your findings.

                                Please do not post inline and offsite as they slow down the loading of pages.

                                --- end sig file ---

                                Comment

                                  #76
                                  Re: MAGNAVOX no picture powers LED 47MF437B/37

                                  When I put it back in the board, I get "001" in both directions again.

                                  I had already removed the Diodes in the burned area.

                                  What could the problem be?

                                  Comment

                                    #77
                                    Re: MAGNAVOX no picture powers LED 47MF437B/37

                                    It sounds like you have shorted load. I am still trying to figure what is connected to the Cathode side (the banded side of the Diode) of this D912.
                                    So you replace the zd902 & zd904 which shown in the picture in the burnt area, but I cannot figure out where this D912 is located on the board.
                                    The reason I ask is that these two Zener Diode are for the Snubber circuits to help protect the MOSFET (Q901 mounted on the heatsink) the drive the switching transformer.
                                    Last edited by budm; 04-15-2012, 06:44 PM.
                                    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

                                      #78
                                      Re: MAGNAVOX no picture powers LED 47MF437B/37

                                      Sorry to be such a pain, It must be frustrating to have someone ask so many questions.

                                      I really do appreciate all the help I am getting from everyone!!

                                      Comment

                                        #79
                                        Re: MAGNAVOX no picture powers LED 47MF437B/37

                                        I haven't replaced the zd902 & zd904 yet. They should arrive here Tuesday or Wednesday.

                                        Should I worry about the "Q901"?
                                        Could it be damaged?
                                        Attached Files
                                        Last edited by scatman0000; 04-15-2012, 07:00 PM.

                                        Comment

                                          #80
                                          Re: MAGNAVOX no picture powers LED 47MF437B/37

                                          Originally posted by scatman0000 View Post
                                          Should I worry about the "Q901"?
                                          Could it be damaged?
                                          Q901 and Q902 are easy to test. Do it in circuit first.

                                          Number the pins 1, 2, and 3. Measure the resistance between 1-2, 1-3, and 2-3. Report your readings for both transistors.
                                          --- begin sig file ---

                                          If you are new to this forum, we can help a lot more if you please post clear focused pictures (max resolution 2000x2000 and 2MB) of your boards using the manage attachments button so they are hosted here. Information and picture clarity compositions should look like this post.

                                          We respectfully ask that you make some time and effort to read some of the guides available for basic troubleshooting. After you have read through them, then ask clarification questions or report your findings.

                                          Please do not post inline and offsite as they slow down the loading of pages.

                                          --- end sig file ---

                                          Comment

                                          Previous 1 2 3 4 5 6 7 template Next
                                          Working...
                                          X