DM800HD rebooting in a loop

Discussion in 'DM800HD Hardware troubles and Repair support.' started by mpro, Jun 17, 2019.

  1. mpro

    mpro New Member

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    Hi
    I have a D800HD that is always rebooting in loop when loading image (it starts loading, then reboots, and the starts loading, a never ending process, in loop)

    If I disconect the tuner the box starts normaly. The tuner is working properly in another DM800HD and also switching the tuner with another one don't solve the rebooting loop problem

    Flashing new image and software don't solve the problem.

    Also tryied another Power Supply without sucess.

    Anyone knows the solution for this problem?

    best regards
     
    Last edited: Jun 17, 2019
  2. Johnny B.

    Johnny B. Technical Support Staff Member Moderator

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    I think, check the motherboard tuner connector main voltages, as also the two 5v caps C255 and C256 and the 3.3v C254 cap.
    As for the voltages check, check it before, and after the inductors.
    More info, see the Tuner or tunerslot issues.
     
  3. oksol

    oksol New Member

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    I solved the problem of rebooting the DM800HD by replacing the 22 mkF electrolytic capacitors on the tuner board with a ceramic one, and C89 (220 mkF) with a low esr.
    Tuner board REV.K
     
    Last edited: Jun 23, 2019
    toysoft and Johnny B. like this.
  4. Johnny B.

    Johnny B. Technical Support Staff Member Moderator

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    Nice to read that you have found a solution for the issue you had, and thanks for sharing it with us.
     
  5. mpro

    mpro New Member

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    Hi my tuner is Rev L3 (ALPS BSBE2-401Am HIG003 REV L3).
    Do you have solution for this?
    The problem is in the tuner (not in the box)
    Best Regards
     
  6. Johnny B.

    Johnny B. Technical Support Staff Member Moderator

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    To be honest, If the solution of the member oksol not helps, then I have no further ideas than to replacing the lmb chip.
    But still, since you say that it must be caused due the tuner, and it is a rev l3, and the motherboards versions are yet unknown, thus assuming you try this tuner on a older motherboard as the rev J.
    then it may also help if you modify the motherboard by adding the resistor as shows here.
    The 510 ohm resistor on top of the capacitor C276 mod which is on newer boards already present.