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NEC PC Engine/TurboGrafx-16 Games/Consoles => Console Repair/Mod Center => Topic started by: TelcoSurveyor on 07/21/2017, 10:08 PM

Title: PC Engine Duo R - No Audio
Post by: TelcoSurveyor on 07/21/2017, 10:08 PM
So I bought a not working Duo R off eBay listed with no sound and no video from the cd drive. I was able to get the cd working beautifully with minor pot adjustments. I ordered a cap kit from Console5 and was looking over the cap diagram and noticed it didn't look like the duo r diagram I had printed out, so I googled the motherboard number and it's a duo rx motherboard inside a duo r shell. Looks like I have a couple less audio circuit caps to replace. Hope it works since I've not heard of the caps needing replaced very often on the duo r's.
Title: Re: PC Engine Duo R - No Audio
Post by: Keith Courage on 07/22/2017, 02:28 AM
Most likely some thing else is at fault. It extremely rare for R or RX systems to have audio issues do to bad caps. Good luck with trying to caps first though.
Title: Re: PC Engine Duo R - No Audio
Post by: TelcoSurveyor on 07/22/2017, 05:42 AM
First thing I did was check the connector for loose solder and discovered there had been an rgb mod done to this, so I swapped the 8 pin for a 5 pin. Still no sound, so my next thought was caps. The board looks in decent shape, but I'm new to looking at it from a troubleshooting standpoint.
Title: Re: PC Engine Duo R - No Audio
Post by: Keith Courage on 07/22/2017, 06:35 AM
Might be a broken trace somewhere or a bad 4558 op amp. rarely ever caps.
Title: Re: PC Engine Duo R - No Audio
Post by: TelcoSurveyor on 07/22/2017, 08:19 AM
I am noticing five of the 4558 op amps that are mounted 2x on the top and 3x on the bottom in the area where the laser is, am I missing any, and should I replace all of them?
Title: Re: PC Engine Duo R - No Audio
Post by: TelcoSurveyor on 07/22/2017, 11:58 AM
Well, I burnt a pad trying to swap C325 and now I think I should send it out to someone who can possibly fix it over me screwing it up further.. Any takers?