Network issues,

Discussion in 'DM800HD Schematic drawings, Pcb images etc..' started by Johnny B., Jun 12, 2015.

  1. Johnny B.

    Johnny B. Technical Support Staff Member Moderator

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    Problem, with or without network cable both network leds on, then off, network failed.



    2290.jpg

    If you have,
    Network, same symptom, with or without network cable both network leds on, then off.
    But the L5 inductor and caps are fine..
    *When you check the serial port with a terminal program as Hyperterminal or Putty, and you receive garbage.
    Replace the Crystal Y1 54.000.

    Or, if you have,
    Network, same symptom, with or without network cable both network leds on, then off.
    But the inductor L5 and caps are fine..
    *When you check the serial port with a terminal progam as Hyperterminal or Putty, and you receive nothing.
    Replace the u17 rs232 ic and probably also the crystal Y1 54.000.

    More info, U10/U18 completely sorted out, also voltage and Ohm measurements.

    DM800hd-networkv3.jpg

    Check also the resistors etc..
    dm800-lan2.jpg
    Resistors are 49.9R 0603 ±1% 1/10W
    Capacitors are 47NF 0603 50V ±20%

    Please also note that internally in the plug there are resistors / caps and coil present.
    Networkconn.jpg
    DM800HD-J1.jpg
     
    raza05 likes this.