• Tony Griffith
    Participant
    Post count: 5
    • Offline
    #512 |

    G’day,
    I have 50PJ350 tv and have replaced the power resistors, diode and regulator ic on the power board. The tv runs for about an hour then goes to standby. It can do this several times and will do the clicking after a few times instead of just standby. Some advice please…Does this sound like the typical symptom that this kit can fix?
    Thanks for any help you may be able to provide.
    Regards
    Tony

  • tech support
    Keymaster
    Post count: 46
    • Offline
    #513 |

    Hi Tony,
    this forum covers several panels and a larger number of Repair Kits targeting differing faults, the Kit I would suggest for this fault given what components you’ve already replaced would be Kit 35, this kit addresses errors in the sampling and feedback circuits used to regulate the power Modules output and stability, and it will likely cure the fault with your Module. Your Module should carry one of these three numbers EAY60968801 / EAY60912401 / EAY60968701, Other areas to check are the solder joints on the main wound components, and just about every device fixed to a heat sink, all these joints may appear fine but they can cause problems especially following manhandling during a repair process.

    kind regards,
    George

  • Tony Griffith
    Participant
    Post count: 5
    • Offline
    #523 |

    G’day George,
    Thanks for the info, I have had the tv running for over 10 hours but today it dropped back to the clicking routine.
    my board is the EAY60968701 module. I’ve bought one of your kits, lets give that a go!
    Regards
    Tony

  • tech support
    Keymaster
    Post count: 46
    • Offline
    #524 |

    Hi Tony,

    Thank you for your confidence in our repair kits and support, this could be a poor solder joint not caught fully the last time, or a thermal fault on a component, if you can still run the TV up from cold you could try using an aerosol freezer to cool suspect components after shutdown and then try to run the TV up again it may throw some light on the situation. However you decide to proceed get back to me and we’ll go the distance together, and full marks for not accepting defeat, good luck with the repair, come back here for support when fitting your kit if you feel it would help

    kind regards,

    George

  • Tony Griffith
    Participant
    Post count: 5
    • Offline
    #617 |

    G’day George,
    Thanks for the marks! lol
    I will get some freeze spray and try that – which components? the power resistors I guess, altho I did replace them. I was wondering if putting 10watt 22 ohm power resistors in instead of the 5 watt 22 ohm may help??

    Something that may or may not be relevant for you – I replaced the regulator and diode first time, the 22ohm power resistors tested ok (cold) so I left them, and the tv would run for 15 mins to an hour and go to stand-by, after 3 or so times of this, then it would start clicking in stand-by….. SO I replaced the power resistors and then the tv looked fixed, I had about 4 lots of 3 hours plus running and then the next day it run for only 20 minutes and then went to stand-by, then come back on, then off, back on and then off and clicking. I noticed the red stand-by light faded out these times, didn’t go off instantly. After this the tv would only do the clicking. That same arvo, I put a fan on the back of the tv to no avail, wouldn’t come on, just clicking This is where I’m up to in testing.

    I’ll check over the soldering, I usually get a shiny wetted joint. Is the factory soldering suspect?

    Thanks for your help
    Regards

  • tech support
    Keymaster
    Post count: 46
    • Offline
    #698 |

    Hi Tony

    All solder joints are suspect and it’s not really a reflection on the Manufacturer, the steel or alloy used on the devices is much harder and has a higher melting point than the solder so you never really get a weld whereby the metals intermix, the best you ever get is a really tight fit, and with the heavier components, movement allows inertia to pull at this tight fit and eventually you see a weakness developing, this is then attacked at a microscopic level by carbon deposits and such as the current attempts to flow through the connection this gradually compromises the conductivity of the connection and a vicious circle develops. This can happen with any joint but is usually worst on the heavier components given Inertia and the typically higher current transfers involved.
    The fault with your TV is thermal so we are either looking at a device breaking down as it reaches operating temperature, or a poor joint/connection failing as it expands with heat, the freezer will be better at highlighting a failing component and will hopefully narrow the search area, the answer to a poor joint is really just close scrutiny and perseverance,

    On the up rating from 5 watt to 10 watt on the resistors, this will enable the resistors to run cooler, which is not a bad thing, but unless they are increasing in value with heat it’s unlikely to be a solution, as they will be larger than the originals and may still run hot, make sure that they are not too close to any plastic cabinet surfaces when the TV is reassembled,

    enjoy your weekend Keith, the UK is forecast for 5 consecutive dry days, that constitutes a Summer here,

    kind regards,

    George

  • Tony Griffith
    Participant
    Post count: 5
    • Offline
    #780 |

    G’day George,
    What a great explanation, I have a much better understanding now. Thanks
    So to attempt a fix of a suspect solder joint, you would put the iron on it to re-heat it?? or would you recommend de-soldering and put new solder in?
    I haven’t got freeze spray yet. I did look for 10w resistors, the problem there is not enough height from the board to the back cover 10w packages 50mm high – the 5w only 25mm high, the inline packages don’t look like the leads are long enough to bring back to place on circuit board. anyways contemplating here.
    I did run tv again today, run for an hour then to clicking and wouldn’t run again (without clicking) So yes thermal issue thanks. Thanks for links and manual I will digest these while waiting for kit. After looking at that vid, I wonder if resistor next to diode near voltage reg, (a shunt -guessing?) may be suspect.
    Anyway thank you for your help and have a good weekend, sound like it will be a good one there.
    Here anything under 20 degrees is cold for me!! and we’re just starting to get day times a bit warmer than that, so it’ll be good weather till end of year when we get about 1 month of too hot! lol we have a whinge each way!!
    Thanks again
    Regards

    Tony

  • tech support
    Keymaster
    Post count: 46
    • Offline
    #1007 |

    Hi Tony,

    reference the re soldering, I always de solder and then re solder, and as I de solder I run the braid along the device pin just a little as I un solder it to give it a gentle rub just to ensure that it has a clean surface to re solder to, the braid/solder mop is inexpensive enough, it also gives you the opportunity to check that the copper solder pad has not cracked and separated from the track this is common with heavier components solder points when a board has had rough handling.
    When you stat with the freezer after obvious targets check the SMD resistors on the solder side of the panel, there is a group of these involved in the sampling and feedback loop the Module uses to regulate its output, if any of these are going high in value the Module will shut down into a protection mode.
    Let me know how you get on Tony,

    regards,

    George

You must be logged in to reply to this topic.