Vu+ UNO4K SE RAM MEMORY REMOVED

Discussion in 'VuPlus Uno Hardware troubles and Repair support.' started by Michal Matas, Jan 2, 2021.

  1. Michal Matas

    Michal Matas New Member

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    Hello guys..I removed ram chip from uno 4kse ..because i was trying repair another receiver..with missing ram..and when i soldered original ram back..receiver not longer boot just blue dot in picture..Then i order new ram chip from ali express..soldered with hotair gun..and still receiver dead..any suggestion ? can be high temperature i soldered ram? or what i can measure now? thanks WhatsApp Image 2021-01-02 at 22.01.32 (1).jpeg WhatsApp Image 2021-01-02 at 22.01.32 (2).jpeg WhatsApp Image 2021-01-02 at 22.01.32 (3).jpeg WhatsApp Image 2021-01-02 at 22.01.32 (4).jpeg
     
  2. Johnny B.

    Johnny B. Technical Support Staff Member Moderator

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    Yeah that is not a simple task to do...

    Placing/solder these balls chips are pretty difficult.
    When I place them it goes often not good because the solder balls are very small and could make easily create a short.

    I have only in most attempts lucky when the motherboard is good cleaned, absolute perfectly level in all direction, and absolutely very good aligned so that it's perfectly placed on the solder spots.

    I always use kapton tape to protect the surrounding area, and use a bga station with a correct profile to solder these on a motherboard.
    And even then, it could in some cases go wrong, often due the room temperature.

    In any case, it's important to not exceed the maximum temperature that is noticed often into the datasheet, in any case not to long, as also it's important to pre heat the motherboard before building slowly up the heat.
    To fast will often fail, the solder balls become often liquidate instead of sinking down as a sort of looking hamburger.
     
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