Strong SRT5300 fails with no bulging electrolytics

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  • japlytic
    Badcaps Legend
    • Oct 2005
    • 2086
    • Australia
    #1

    Strong SRT5300 fails with no bulging electrolytics

    In a Strong SRT5300, I found that when the unit is turned on, all of the segments on the front display are stuck on.
    Measuring the power supply rails shown that the +3.3V rail was low, along with the +5V rail a bit too high .
    Replacing all of the electrolytic capacitors except the 400V unit fixed the problem and has shown that no damage was caused by a high +5V rail.

    The electrolytics on the power supply board were mainly Samyoung SHL and KME Series units, which were unsuitable for switching power supply service .
    My first choice in quality Japanese electrolytics is Nippon Chemi-Con, which has been in business since 1931... the quality of electronics is dependent on the quality of the electrolytics.
    Tags: None
    • stj
      Great Sage 齊天大聖
      • Dec 2009
      • 31084
      • Albion
      #2
      Re: Strong SRT5300 fails with no bulging electrolytics

      that's standard crap, i used to fix hundreds of sat boxes.
      i never checked them first, just replaced all the caps and 99.9% of them started up and never failed again.
      the few times it still wasnt right, the ripple had corrupted the flash - a reflash of the firmware & they also never came back.

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