What to replace an unobtainable bipolar elctrolytic?

Collapse
X
 
  • Time
  • Show
Clear All
new posts
  • Amminadabz
    New Member
    • Jul 2022
    • 2
    • USA

    #1

    What to replace an unobtainable bipolar elctrolytic?

    Howdy folks, its been a minute.

    I'm working on a capacitor kit for my Korg C-15 digital piano, and it has a couple bipolar electrolytics (C27 and C34) on the analog board for which I can only find one direct replacement, but it's sold in multiples of 50.

    I've got a couple work-arounds in mind (Ebay NOS, testing with the og part, swapping for a ceramic), but what part can I recommend that will be reliably obtainable in the future? Would a ceramic or MLCC (not entirely sure what the practical difference is) be a good general replacement for bipolar electrolytics? It's hard to find succinct information about this.
  • petehall347
    Badcaps Legend
    • Jan 2015
    • 4425
    • United Kingdom

    #2
    Re: What to replace an unobtainable bipolar elctrolytic?

    film so long as its not too large .

    Comment

    • lti
      Badcaps Legend
      • May 2011
      • 2547
      • United States

      #3
      Re: What to replace an unobtainable bipolar elctrolytic?

      I would also suggest film caps for an audio circuit like that. The schematic I found shows that they're just coupling caps on the amp input. Kemet R82 and TDK B32529 series seem readily available and small enough that they should fit.

      Comment

      • bestsystem
        Senior Member
        • May 2011
        • 59

        #4
        Re: What to replace an unobtainable bipolar elctrolytic?

        get nichicon muse BP , 1.0uf, 2.2 or even 4.7uf won't go wrong for coupling.

        According to audio circuit books by Douglas Self, reasonably oversized coupling electrolytic caps give less distortion.

        Comment

        • lti
          Badcaps Legend
          • May 2011
          • 2547
          • United States

          #5
          Re: What to replace an unobtainable bipolar elctrolytic?

          Nichicon discontinued all of their smaller caps. Those bipolar audio caps were my first thought as well.

          I did see a Rubycon NW7 series cap in stock on Mouser, so that's an option if you don't want to switch to film caps. It will be smaller than the original.

          If you increase capacitance, there are a lot more bipolar electrolytic options.

          Comment

          • bestsystem
            Senior Member
            • May 2011
            • 59

            #6
            Re: What to replace an unobtainable bipolar elctrolytic?

            Originally posted by lti
            Nichicon discontinued all of their smaller caps. Those bipolar audio caps were my first thought as well.

            I did see a Rubycon NW7 series cap in stock on Mouser, so that's an option if you don't want to switch to film caps. It will be smaller than the original.

            If you increase capacitance, there are a lot more bipolar electrolytic options.
            it should be ok to increase to a few uF without major issue, if a design is critical to excess coupling cap capacitance or inrush charge up time constant, then film cap would have been chosen instead.


            I have a build mic peramp that got a 220uf coupling cap between 2nd~3rd opamp stages, 5k ohm resistor to ground in 3rd stage, takes me 2 senconds to settle when powering on before recording, all are fine.

            Comment

            Related Topics

            Collapse

            • Adenitz
              Replace electrolytic cap with bipolar one
              by Adenitz
              Hello,
              can I use this cap:
              https://www.tme.eu/en/details/ues1h4...tors/nichicon/

              Capacitor: electrolytic; bipolar; THT; 47uF; 50V

              to replace this capacitor: Electrolytic Radial E 47uF/50V 6.3x11 RM2.5 105°C Jamicon

              What exactly I can expect to install bipolar electrolytic cap instead a regular one?

              Thanks.
              02-02-2022, 07:44 AM
            • tony359
              Bipolar capacitor for vintage Apple CRT monitor
              by tony359
              Good day all,

              I have a question about some old monochrome Apple monitors.

              Inside those monitors there is one bipolar capacitor. From the schematics I have it's part of the horizontal linearity circuit.

              A friend replaced a bipolar 4.7uF 25V capacitor with a Nichicon bipolar 4.7uF 25V. The cap popped after about one hour. The new capacitor was much smaller than the original one but that's not a surprise as the original one was from 1980. (I am not sure whether the original was was actually 4uF and was replaced with a 4.7uF?)

              The new capacitor:...
              08-12-2024, 03:27 AM
            • Exim
              Yamaha YST-MS25 amp board recap: replace small electrolytics with different type?
              by Exim
              Hi there, I'm working on the 25W amp board of a Yamaha YST-MS25. It's 20yrs old.
              Since a few months the volume on the left channel is way too low. It turned out that - compared to the intended use and the former price tag of this thing - they put solid stuff into it. So I decided it's worth a recap.

              The board uses two amp ICs on opposite sites of the board. Both ICs are connected to the same heatsink. The heatsink unfortunately is a bridge-like construction that covers almost all other components, including the majority of the caps (pictures and schematics below).
              ...
              10-31-2018, 04:11 PM
            • Cap_search
              Question about bipolar electrolytics
              by Cap_search
              Good morning all,

              Is it true that all the bipolar electrolytics are made/manufacturered of two "back-to-back" polar electrolytics in the - + + - configuration, and that would explain why they are usually larger than equivalent value of a common polarized electrolytic? (e.g. Muse UES)

              N.B.: polarized Silmic II are also usually larger than common electrolytic, though.
              07-22-2019, 02:45 AM
            • chth96
              Is it no harm to replace with capacitor without ripple current rating?
              by chth96
              When I tried to repair LG 29 inch CRT TV, I found that the ESR value of samyoung SMS capacitor(160v 2.2uf), which is very close to D1879 transistor, is 6 ohm.


              Judging from above ESR Meter Table,I think It is necessary to replace this sms capacitor.So I visited local electronics shop,and I purchased 160v 2.2uf rubycon YK capacitor.
              But when I browse through rubycon YK datasheet,I found that there is no ripple current rating for 160v 2.2uf specification. But On the contrary, I found 39 mA ripple current rating for 160v 2.2uf SMS capacitor.
              Rubycon YK DataSheet (b...
              04-19-2024, 05:19 AM
            • Loading...
            • No more items.
            Working...