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Thread: Homebrewness repairs for the masses?

  1. #1
    Orca Whisperer kf0rt's Avatar
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    Homebrewness repairs for the masses?

    Unimpressive linky:

    http://techreport.com/forums/viewtop...sd=a&start=150

    Story:

    Coupla weeks ago, my wife started complaining that our TV was doing a lot of clicking before it turned on. Sometimes, it would click for 30 seconds or so before it'd finally come on. This is a 46" Samsung LCD that we got for Christmas a little over two years ago (love it, BTW).

    Got to digging around on the web today, and found that the problem is somewhat common. Remember the "bulging capacitor" problem that plagued computer motherboards a couple years ago? Seems some of those caps made it into the power supplies of Samsung TV's. When they start to go, the power relays start clicking and eventually the power circuit fails.

    "Borrowed" a couple caps from the E-Lab at work (which has been dormant since the last layoff ) and after an hour or so (mostly screwdriver time), had the problem fixed.

    What amazes me, though, is the number of folks who seem willing to tackle something like this with no real electronics background at all:

    not very tech savvy, my husband tried to desolder the old capacitors but wasn't having any luck, no experience soldering. so took it to electronic repair shop to have the capacitors changed. the guy said it was soldered with silver and sealed (whatever that means). anyway he changed the capacitors (for free! just asked me to make donation to shriners childrens hospital).
    Just wanted to add my thanks to the resident experts who offered detailed direction. Was able to fix my TV for $9.42.

    Was afraid to try this till my stepson called and said the magic words ......... "I solder". Only took us about 35 minutes!!!
    I found out the problem was just two simple caps on my power supply that were bulged out just enough to tell. (CM852 & CM853) Im lucky theres a liquidation wharehouse not far from my house that sells brand new caps for 15 CENTS!!! Thats right I couldnt believe it either, that is until I got them home and did the 20 minute job of replacing them. They were easy to replace as I have a little solder experience and I already had the right tools. The tv powered right on with NO CLICKING for the first time in months!!! Total cost of job: 30 CENTS!!! And 20 minutes of my time.
    2. Went to Radio Shack and bought 2 1000uf, 35Volt capacitors (See Picture 7) Cost: $1.59 each plus tax
    3. Bought a cheap 5pc soldering iron and kit, including 60/40 rosin core solder Cost: $7.99 plus tax
    Kinda floors me that a lotta folks with no electronical experience and have never soldered before would dig into a TV that cost them $3,000.

  2. #2
    "Island Bartender" KG4CGC's Avatar
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    Re: Homebrewness repairs for the masses?

    Quote Originally Posted by kf0rt
    Unimpressive linky:

    http://techreport.com/forums/viewtop...sd=a&start=150

    Story:

    Coupla weeks ago, my wife started complaining that our TV was doing a lot of clicking before it turned on. Sometimes, it would click for 30 seconds or so before it'd finally come on. This is a 46" Samsung LCD that we got for Christmas a little over two years ago (love it, BTW).

    Got to digging around on the web today, and found that the problem is somewhat common. Remember the "bulging capacitor" problem that plagued computer motherboards a couple years ago? Seems some of those caps made it into the power supplies of Samsung TV's. When they start to go, the power relays start clicking and eventually the power circuit fails.

    "Borrowed" a couple caps from the E-Lab at work (which has been dormant since the last layoff ) and after an hour or so (mostly screwdriver time), had the problem fixed.

    What amazes me, though, is the number of folks who seem willing to tackle something like this with no real electronics background at all:

    not very tech savvy, my husband tried to desolder the old capacitors but wasn't having any luck, no experience soldering. so took it to electronic repair shop to have the capacitors changed. the guy said it was soldered with silver and sealed (whatever that means). anyway he changed the capacitors (for free! just asked me to make donation to shriners childrens hospital).
    [quote:28r4diwr]Just wanted to add my thanks to the resident experts who offered detailed direction. Was able to fix my TV for $9.42.

    Was afraid to try this till my stepson called and said the magic words ......... "I solder". Only took us about 35 minutes!!!
    I found out the problem was just two simple caps on my power supply that were bulged out just enough to tell. (CM852 & CM853) Im lucky theres a liquidation wharehouse not far from my house that sells brand new caps for 15 CENTS!!! Thats right I couldnt believe it either, that is until I got them home and did the 20 minute job of replacing them. They were easy to replace as I have a little solder experience and I already had the right tools. The tv powered right on with NO CLICKING for the first time in months!!! Total cost of job: 30 CENTS!!! And 20 minutes of my time.
    2. Went to Radio Shack and bought 2 1000uf, 35Volt capacitors (See Picture 7) Cost: $1.59 each plus tax
    3. Bought a cheap 5pc soldering iron and kit, including 60/40 rosin core solder Cost: $7.99 plus tax
    Kinda floors me that a lotta folks with no electronical experience and have never soldered before would dig into a TV that cost them $3,000.[/quote:28r4diwr]
    Without getting political...........................
    is it because the economy sucks?

  3. #3
    Orca Whisperer kf0rt's Avatar
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    Re: Homebrewness repairs for the masses?

    Quote Originally Posted by KG4CGC
    Without getting political...........................
    is it because the economy sucks?
    That did kinda cross my mind...

  4. #4
    Administrator N8YX's Avatar
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    Re: Homebrewness repairs for the masses?

    Necessity is the mother of invention.

    Of all those "bad caps", I wonder how many are being run at or over their voltage or temperature maximums then failing as a result? And when Harry Homeowner replaces them with an equivalent part that's also under-spec'd for the application... :roll:
    "Everyone wants to be an AM Gangsta until it's time to start doing AM Gangsta shit."

  5. #5
    Forum Addict w3bny's Avatar
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    Re: Homebrewness repairs for the masses?

    what would be more teh funneh would be if that was a CRT based tv and he decided to get hooked up on the wrong side (as if there is a right side) of the flyback transformer.

    whhheeeeeezeeehhhKAPOW! <thud>
    Yeah...I'm a furry...Deal with it!

  6. #6
    "Island Bartender" KG4CGC's Avatar
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    Re: Homebrewness repairs for the masses?

    flyback transformer
    :rofl:

  7. #7
    SK Member (12/2/2011)
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    Re: Homebrewness repairs for the masses?

    Electrolytic caps are just like the old song, "It's Just a Matter of Time".

    http://popup.lala.com/popup/360569526775414312

  8. #8
    'Grumpy old bastid' kb2vxa's Avatar
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    Re: Homebrewness repairs for the masses?

    Yup, flyback transformer, the part with the funny name and the source of countless really bad jokes.
    "The universe is under no obligation to make sense to you."
    Neil deGrasse Tyson

    73 de Warren KB2VXA
    Station powered by atomic energy, operator powered by natural gas.

  9. #9
    Orca Whisperer kf0rt's Avatar
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    Re: Homebrewness repairs for the masses?

    Quote Originally Posted by N8YX
    Necessity is the mother of invention.

    Of all those "bad caps", I wonder how many are being run at or over their voltage or temperature maximums then failing as a result? And when Harry Homeowner replaces them with an equivalent part that's also under-spec'd for the application... :roll:
    One does wonder... Most of the repair advice I read on this particular subject suggested going with a higher voltage replacement, but without any confirmed reason. The caps I pulled out were all rated at 105C -- set gets warm, but nothing like a tube TV. I replaced the 2200uf / 10v caps with 2200uf / 16v and the 1000uf / 25v caps with 1000uf / 35v, but the junquebox I had access to only had 85C parts.

    Without researching, isn't 105C mil-spec and 85C commercial? Seems like Samsung may have had good intentions in their part specs. Bad caps were of the "Samwha" brand (Korean), and their logo looks suspiciously like the Samsung logo. :chin:

    TV was assembled in Tijuana. :shock:

  10. #10
    Administrator N8YX's Avatar
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    Re: Homebrewness repairs for the masses?

    Quote Originally Posted by kf0rt
    Without researching, isn't 105C mil-spec and 85C commercial? Seems like Samsung may have had good intentions in their part specs. Bad caps were of the "Samwha" brand (Korean), and their logo looks suspiciously like the Samsung logo. :chin:
    105C spec would be more than adequate, assuming a voltage rating of 40-50% above normal circuit levels. Problems arise when the caps are run too close to their maximums then develop holes in the dielectric due to repetitive spiking.

    Certain Icom receivers were notorious for this...the DC-DC converter (which develops -20v for the display tubes) used capacitors whose working voltages were extremely close to the DC levels encountered in the circuit. Just add heat and you can guess the rest.
    "Everyone wants to be an AM Gangsta until it's time to start doing AM Gangsta shit."

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