Cap help

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  • MST246
    New Member
    • Jul 2015
    • 7
    • usa

    #1

    Cap help

    Hi Folks

    I'm in need of some direction regarding cap replacement.After 12 trouble free years of bang and boom,my JBL E250P blew out C72 (6.8uf 100v non-polar blah,blah, blah) you guys know the deal here.

    If understand correctly,guys are replacing this cap with a film cap.I will no doubt ask some stupid questions but it can't be helped.

    After all the searching I'm getting bug eyed,a headache and pulling out whats left of my hair.

    So,let the fun begin,is this what I'm looking for?

    http://www.digikey.com/product-detai...F1685-ND/56410

    Here come some stupid questions.

    1. How to tell the polarized from non-polarized film caps,if they come both ways that is,I don't see anything in the specs
    (warned you about the ?'s)

    2. Does lead length and spacing matter here?

    3. How close to the board should these be attached.

    Thanks
  • stj
    Great Sage 齊天大聖
    • Dec 2009
    • 30930
    • Albion

    #2
    Re: Cap help

    film caps arent polarised

    Comment

    • budm
      Badcaps Legend
      • Feb 2010
      • 40746
      • USA

      #3
      Re: Cap help

      If you look at the old electrolytics bi-polar original cap, you will see that it is a lot smaller than the replacement film cap type, JBL uses the electrolytics type because it is cheaper but they do not last, that cap is part of the Class D power amplifier output filter cap.
      You should also replace the C73 4.7uF at the same time. See service manual.
      See if you have room to put those two new caps in place of the old one, just try to keep the lead length as short as possible and you will be fine.
      JBL is not the only company that cheap out on these caps by using electrolytics in stead of film caps. I have seen so many failure of these caps in the output filter section of these Class D amplifiers.
      Attached Files
      Last edited by budm; 07-25-2015, 08:57 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

      • MST246
        New Member
        • Jul 2015
        • 7
        • usa

        #4
        Re: Cap help

        Originally posted by budm
        If you look at the old electrolytics bi-polar original cap, you will see that it is a lot smaller than the replacement film cap type, JBL uses the electrolytics type because it is cheaper but they do not last, that cap is part of the Class D power amplifier output filter cap.
        You should also replace the C73 4.7uF at the same time. See service manual.
        See if you have room to put those two new caps in place of the old one, just try to keep the lead length as short as possible and you will be fine.
        JBL is not the only company that cheap out on these caps by using electrolytics in stead of film caps. I have seen so many failure of these caps in the output filter section of these Class D amplifiers.
        I was thinking about C73 also. I may just have to make room in the rubbery gunk the old caps sit in.Also is it true about C65 being incorrect 470uf that should be 47uf to stop chirp upon waking up? Is that even a problem?
        Thanks to all for getting back.

        Comment

        • budm
          Badcaps Legend
          • Feb 2010
          • 40746
          • USA

          #5
          Re: Cap help

          I do not see any TECH TIP in the service manual regarding to the cap values changed from what are shown in the diagram, may be you should contact JBL to see if they release any service bulletin for this model.
          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

          • MST246
            New Member
            • Jul 2015
            • 7
            • usa

            #6
            Re: Cap help

            Originally posted by budm
            I do not see any TECH TIP in the service manual regarding to the cap values changed from what are shown in the diagram, may be you should contact JBL to see if they release any service bulletin for this model.
            It's all over the net,but does not bother me.Right now trying to find film replacement for C73 4.7uf 50v but the filters show 100 and 250 for options,is ok to go higher on the volts?

            Comment

            • stj
              Great Sage 齊天大聖
              • Dec 2009
              • 30930
              • Albion

              #7
              Re: Cap help

              yes, if you can make it fit.

              Comment

              • budm
                Badcaps Legend
                • Feb 2010
                • 40746
                • USA

                #8
                Re: Cap help

                Originally posted by MST246
                It's all over the net,but does not bother me.Right now trying to find film replacement for C73 4.7uf 50v but the filters show 100 and 250 for options,is ok to go higher on the volts?
                Is your chirping? To go 10 times less capacitance seems like a big change that I would think JBL will have service bulletin out.
                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

                • MST246
                  New Member
                  • Jul 2015
                  • 7
                  • usa

                  #9
                  Re: Cap help

                  Originally posted by budm
                  Is your chirping? To go 10 times less capacitance seems like a big change that I would think JBL will have service bulletin out.
                  They all do it,but I think it's by design.Someone may have figured out a way to quiet it down.How about the other part of my question about the volts on the 4.7 C73.Thanks

                  Comment

                  • MST246
                    New Member
                    • Jul 2015
                    • 7
                    • usa

                    #10
                    Re: Cap help

                    Originally posted by budm
                    Is your chirping? To go 10 times less capacitance seems like a big change that I would think JBL will have service bulletin out.
                    They all do it,but I think it's by design.Someone may have figured out a way to quiet it down.How about the other part of my question about the volts on the 4.7 C73.Thanks

                    Comment

                    • budm
                      Badcaps Legend
                      • Feb 2010
                      • 40746
                      • USA

                      #11
                      Re: Cap help

                      Higher Voltage is fine but the body size will increase with the higher Voltage rating.
                      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

                      • MST246
                        New Member
                        • Jul 2015
                        • 7
                        • usa

                        #12
                        Re: Cap help

                        Thanks for help guys,I may end up going with a known good brand elec for C73 just save one headache.

                        Comment

                        • jmonica
                          New Member
                          • Dec 2018
                          • 2
                          • United States

                          #13
                          Re: Cap help

                          I know this very helpful post is 3+ years old. Apparently Film type capacitors have gone down in price because unlike what was posted in terms of JBL being too chip to use Film type caps, film caps seem to be a LOT less expensive than the older type. I can buy 100 Film type capacitors for less than I can buy 1 Electrolytic capacitor with the same rating. It has me concerned now that I am not buying the right thing. Oh well what's the worst that can happen? Fry the rest of the Amp board? Its not working anyway. Electrocute myself? Can't find the upside to that one. Burn down my house and the houses surrounding mine? I'm insured.

                          Comment

                          • jmonica
                            New Member
                            • Dec 2018
                            • 2
                            • United States

                            #14
                            Re: Cap help

                            Originally posted by jmonica
                            I know this very helpful post is 3+ years old. Apparently Film type capacitors have gone down in price because unlike what was posted in terms of JBL being too chip to use Film type caps, film caps seem to be a LOT less expensive than the older type. I can buy 100 Film type capacitors for less than I can buy 1 Electrolytic capacitor with the same rating. It has me concerned now that I am not buying the right thing. Oh well what's the worst that can happen? Fry the rest of the Amp board? Its not working anyway. Electrocute myself? Can't find the upside to that one. Burn down my house and the houses surrounding mine? I'm insured.
                            I'm an idiot. I thought Mylar Film capacitors were the type of film caps mentioned. I was wrong. The correct Film type caps ARE in fact way more expensive. That why morons like me shouldn't comment on well, anything.

                            Comment

                            • stj
                              Great Sage 齊天大聖
                              • Dec 2009
                              • 30930
                              • Albion

                              #15
                              Re: Cap help

                              polypropylene film.

                              Comment

                              • redwire
                                Badcaps Legend
                                • Dec 2010
                                • 3900
                                • Canada

                                #16
                                Re: Cap help

                                Polypropylene are hard to find in low voltage. They are usually >250V and physically big, and ~4X the cost of Polyester/Mylar.
                                Anyone know what this cap does in the JBL? Crossover?

                                Comment

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