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REPAIR GUIDE - TurboDuo: Sound Fix

Started by D-Lite, 09/01/2005, 12:27 AM

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SiberianSpForces

The Sound Issueâ„¢ popped up on my Duo this past week. Found leakage from one of the three 4.7 caps right next to the jack/volume dial and under the 1k cap. I replaced all four of the 4.7's and the 1k. Haven't had the chance to sit down with the Duo for a couple of hours to test it out yet.

Enchurito

So after trying to get my system going I've got the CD drive working (had crud in the gears) however still zero sound. Pictured is my board
/c0rrm.jpg

SiberianSpForces

Take your phone flashlight or something equivalent and look at the bottom of the caps. Especially the ones around the AV and headphone ports. Maybe the AV port solder joints need reflowed.

Keith Courage

Quote from: Enchurito on 11/21/2017, 05:00 PMSo after trying to get my system going I've got the CD drive working (had crud in the gears) however still zero sound. Pictured is my board
/c0rrm.jpg
Ugh, no fun working around the gamedoctorHK region mod.

Anyways, there could be a number of reasons why you have no audio. However, being that you have no audio at all I would check the 4558 op amp just to the right of the AV jack. Lots of times old cap goo can get underneath these and short things out. The contacts can also corrode. 95% of the time the op amp can be removed, contacts cleaned, then re-soldered and all is good again. In some cases new leads/wires have to be soldered in to fix corroded contacts on the board and in more rare cases the op amp has to be replaced. Also, check that the op amp is getting around 3.8V from the 22UF next to it.

mickcris

Quote from: Keith Courage on 12/08/2017, 07:23 AM
Quote from: Enchurito on 11/21/2017, 05:00 PMSo after trying to get my system going I've got the CD drive working (had crud in the gears) however still zero sound. Pictured is my board
http://i66.tinypic.com/c0rrm.jpg
Ugh, no fun working around the gamedoctorHK region mod.
Yeah, it sucks they only replace certain caps.  they should just replace them all while they are at it and clean the board.  but that would eat into profits i guess.

mtrienis

Hi, where is the diagram for this post?

esteban

Quote from: mtrienis on 12/31/2017, 12:17 PMHi, where is the diagram for this post?
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Keith Courage

Quote from: mtrienis on 12/31/2017, 12:17 PMHi, where is the diagram for this post?
at the time of this original post it showed how to replace just a few of the capacitors on the board to get the sound working again. Overtime, this has proven to not do much at all anymore since really all the capacitors in the system should be changed. there are other caps on the board that can affect the sound besides the ones initially mentioned in this post.

so if you are experiencing sound issues, just change all the capacitors.