Tuner empty

Discussion in 'DM800HD Hardware troubles and Repair support.' started by jeet999, Aug 6, 2017.

  1. jeet999

    jeet999 New Member

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    dear sir please help i have dm800hd its tuner no searching signal what is problem
    tuner BSBE2-801A
    CLK OUT PIN 2.0 MV OUT OF 1.72
    LNB RF POWER INPUT PIN .70 MV
    box is empty no have any channels
    what i can do..



    dm800-tuner-modules-vdc-ohms_LI.jpg dm800-tuner-modules-vdc-ohms_LI.jpg HG001-01-Tuner-connector_LI.jpg dm800-tuner-modules-vdc-ohms_LI.jpg HG001-01-Tuner-connector_LI.jpg dm800-tuner-modules-vdc-ohms_LI.jpg HG001-01-Tuner-connector_LI.jpg IMAG0383.jpg IMAG0384.jpg IMAG0385.jpg IMAG0386.jpg
     
  2. jeet999

    jeet999 New Member

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  3. jeet999

    jeet999 New Member

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    tunerslot-drawing-with-without-tuner_LI.jpg
    without tuner all voltage measurement is ok showing as this fig but with tuner some point 21,52,53,56 different

    53 point ov
     
    Last edited: Aug 6, 2017
  4. Johnny B.

    Johnny B. Technical Support Staff Member Moderator

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    The lower voltage measurements are not the reason, these may become lower due a inactive, or other type tuner.
    It could be a tuner issue, thinking of a bad U500-LNBP21PD, or related to the software which is in most cases due the software, the tuner drivers.
    In any case, based on the information I have no reason to think that it is a issue from the motherboard hardware.

    Also, Eardatek, rev M tuners gives more often this problem, better would be if you could try it with another tuner.
    Or else, try another power supply, one with more amps, in any case 3 to 5 amps should be better because these tuners uses a bit more amps that others.

    Try also other software as openpli or openatv to see if it brings the tuner back to live.
    Nevertheless these advice's are also based on a good working dish system, which I may assume that you have test it.
     
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  5. jeet999

    jeet999 New Member

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    thanks sir for reply
    LNBP21PD voltage measurements are
    pin ..... volt
    1 2.2mv
    2 34.2mv
    3 18mv
    4 2.2mv
    5 3.3mv
    6 2.2mv
    7 2.0mv
    8 4.97 v
    9 2.6mv
    10 2.2mv
    11 2.0mv
    12 3.25 v
    13 3.25 v
    14 2.2mv
    15 3.16 v
    16 2.2mv
    17 2.2mv
    18 11.94 v
    19 11.80 v
    20 2.2mv

    it's ok mother bord no issue i cheked other tuner working fine
    how can do
     
  6. Johnny B.

    Johnny B. Technical Support Staff Member Moderator

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    Because you have the 5v on the pin 8 (byp) it seems that the lnb chip is working, also you have the 12/13 scl/sda 3v and 18/19 12v.
    And because you say that you don't have at least the 12v on the lnb, then i'm thinking of a interruption of the inductor L502, 0r a issue with the coil L510, or diode D500.
    In any case, a diode or inductor, or coil from/to the lnb chip may cause this issue.
     
  7. Johnny B.

    Johnny B. Technical Support Staff Member Moderator

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    By reading this.. box is empty no have any channels.
    Without a channel list the lnb rf input could be 0 volts.
    Better is to add a channel list manually to see if you get a voltage on the lnb input.
    At the other hands, when scanning channels, the lnb rf input must give the 12/18v dc, even without a dish system connected.
    It only have no voltages when it is not set on a channel.

    In any case, I've found a picture which shows the lnb circuits on the tuner.
    Maybe it helps a bit with finding the issue.

    dm800hd-tuner-revm-lnb-circuit.jpg