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Question about Sanyo HT30744 TV

2 Answers

Hum, Rumble,Pop...Signal Loss

I have had my set for two years and recently starting having a problem with the sound intermittently when someone walked by the set (old wood floors transmit vibration to set). The problem worsened and now the slightest disruption causes the audio to hum, then sound like loud wind noise on a microphone and finally a pop and the video and audio are both gone. I discovered that the picture and sound can be restored by lifting on the cables for the component input from my DVD player. This led me to believe that I had a bad solder joint on the board from torqing the cables during installation. By the way, the problem remains even if the component input cables are all removed. Upon close inspection, the solder looked intact, but I noticed that Sanyo used only two of the five screw holes they engineered to stabilize the inputs. I soldered the connections at the board even though they looked good and added screws to all of the holes (location for holes is visible on inside of the cover) for more stability. Adding the screws made it much more stable, so I had high hopes. But the he problem remains. Is the problem in the the component connector itself? Am I destined for the repair shop?

Posted by Matt Hirn on

  • 1 more comment 
  • Matt Hirn Jul 30, 2007

    If things weren't bad enough, now the set loses all of its set-up information after each use. I now have to search for channels before I can start viewing upon every start-up. Anyone seen this problem before?

  • Matt Hirn Jul 31, 2007

    Thanks Silverdragon for your advice. I have called a repair shop. There would be a bare minimum $75 bench fee and the tech guessed that it may cost $175 to fix (suspects a bad ground somewhere). It could be more costly though. The set was only $400 new. Should I bother fixing it? Dare I take out the board and start looking for a bad solder joint elsewhere myself? I am an electronics novice. I know enough to steer clear of capacitors, but serious electronics troubleshooting is not in my skill set.

  • Matt Hirn Jul 31, 2007

    After both Silverdragon and a local tech said that it sounded like a cold solder joint somewhere on the board, I took the board out to fix it myself. I blanket-soldered everything on the end of the board near component inputs. After about two hours of work the set was back together and working fine.

    Thanks again Silverdragon for pointing me in the right direction.



2 Answers

Sérgio Dias

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That is a dry joint "beat in left side of tv if fail´s its a dry joint for sure"....sorry my english

Posted on Feb 04, 2008


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Yup ya off to the "Shop" me thinks this type of fault is a nightmare to fix, generally.. any intermittent one but in saying this any serviceman worth his/her salt should be able to fix it in a hour or two.. I like you would suspect a "Dry Joint" or bad connection.. Make sure you get a firm "Quote" B4 proceeding.. good Luck

Posted on Jul 31, 2007


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