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Equipment Repairs => LCD TV forum => Topic started by: Turnip on March 26, 2014,09:04:16

Title: Sharp LC-40F22E 17MB61-2 Sound problem
Post by: Turnip on March 26, 2014,09:04:16

Hi folks,

Got one of these in where set is OK for a while, then sound slowly distorts to something like a Dalek. Note the sound chip appears one of those horribly small ones.

Any thoughts - Thanks - Chris.

Title: Re: Sharp LC-40F22E 17MB61-2 Sound problem
Post by: jordan on March 26, 2014,10:22:38

Replace 4 SMD capacitors (0,47uF) on audio input (RINP,RINN,LINP,LINN) with new 1uF capacitors

Title: Re: Sharp LC-40F22E 17MB61-2 Sound problem
Post by: Turnip on March 26, 2014,10:37:34

Hi Jordan and thanks,

Will go look for those caps - I gave the chip (MAX9736A) a squirt of freezer, and sound was again normal. Don't suppose anyone has a shematic  - Bit doubtful that I could manage change it though, as it doesn't seem to have extended pins and the area is congested.

Impressed though with something that can deliver 30 or so class D watts and is the size of a flea's whatsit.

Thanks again - Chris.

Title: Re: Sharp LC-40F22E 17MB61-2 Sound problem
Post by: downunder on March 27, 2014,04:46:20

Hey Turnip, time to call The Doctor !! Any chance to heatsink it...some quite nifty glues out there these days, or perhaps try one of them rubber thingies ....heat transfer pads. Else it's the main board and a big
hit to your bank account.

Title: Re: Sharp LC-40F22E 17MB61-2 Sound problem
Post by: Turnip on March 27, 2014,05:10:59

Thanks Bruce,

Chip doesn't actually run hot when sound is distorted, so think a panel the answer - Noticed some on the Flea.

Thanks again - Chris.

Later - Discovered ChasHyde has a repair kit with Jordon's 4 caps and U168 chip. Caps so small they send 8 should you lose some. Had a look at shematic and attach a piccy outlining suspect caps C1075/6/7/8

Title: Re: Sharp LC-40F22E 17MB61-2 Sound problem
Post by: old tvman on March 28, 2014,07:52:58

Very common problem with the audio o/put IC on these chassis,TPA3113D2  causes int no/distorted sound.

Title: Re: Sharp LC-40F22E 17MB61-2 Sound problem
Post by: Turnip on March 28, 2014,11:51:58

Hi TVOM and thanks,

Output chip is Maxim Max9736A - Your chip appears to be audio control, where those caps C1075/6/7/8 need changing 0.47 to 1mfd. Gather TPA3113D2 is sometimes the problem.

I did it the easy way and got a panel from Fleabay, plus a bag of 1mfd SM ceramics from China for the next one.

Thanks again - Chris.

Later - Gather the TPA3113D2 is a 6 x 6 watt output chip, my panel 61-2 doesn't have one. The Maxim chip 15 + 15 watt was the problem.