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  1. Member
    Join Date: Nov 2007
    Location: Portugal
    Search Comp PM
    Was hoping it was just some bulged caps but can't find any. I have a half decent multimeter but don't know how to test the power board. Already identified the rails on the connector that goes to the main board that don't have power. But could that be because the power button is necessary to get it started ? In that case there must be some pins that have to be shorted to simulated the power on. There's some strange noises coming from it, very low in noise but noticeable if you put your ears close, don't think it's normall...

    Any help ?

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  2. Mod Neophyte Super Moderator redwudz's Avatar
    Join Date: Sep 2002
    Location: USA
    Search Comp PM
    You have probably checked for most of the obvious faults, burned parts in the power supply module, blown fuses or the obvious smell of burned parts. I've no idea whether the power switch switches the mains power directly or through a switching transistor like a PC does. Try tracing the switch leads back to the PS.

    You can get odd sounds out of a high frequency switching PS.

    Unless someone here has some better ideas, you should be able to find a service manual online for a price by doing a search for:
    ' Panasonic DMR-EH60 service manual '
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  3. Member turk690's Avatar
    Join Date: Jul 2003
    Location: ON, Canada
    Search Comp PM
    Originally Posted by JoseD View Post
    Was hoping it was just some bulged caps but can't find any.
    Some defective electrolytic capacitors do not necessarily appear bulged/popped open nor have a way-out-of-spec capacitance reading. An ESR meter can find out, but that can be too much work. So with DVD players, recorders, set-top boxes, etc I just replace all electrolytic caps on the PSU. Some of the capacitors will be surface-mount types; they also have to be replaced (which may complicate matters to the non-professional). Other tips:
    • There may be a mechanical switch (to completely power off the unit, compared with being on just standby); check it.
    • The soft power-on button can also become defective (permanently open); this can be checked with a tester.
    • Normally, there is always some sort of standby voltage line (commonly +5Vdc, sometimes +3.3Vdc) that will always be on, to power the processor/remote control circuit. If this voltage is missing, power to the main B+ lines can't be applied even if front panel/remote control on/off button is pressed.
    • There are many types of switch-mode PSU circuit design, at least where AC mains goes into. If the fuse didn't blow, and there is a single line filter capacitor (usually rated 400V or 450Vdc, in 220Vac countries), then at standby power about +320 to +360Vdc should be measured across it. If it's the half-wave voltage doubler type and there are two input filter capacitors, each should have +100 to +150Vdc across. These are dangerous high voltages so poke at your own risque.
    Last edited by turk690; 12th Oct 2013 at 00:18.
    For the nth time, with the possible exception of certain Intel processors, I don't have/ever owned anything whose name starts with "i".
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