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NEC TG-16/TE/TurboDuo => TG/PCE Repair/Mod Discussion => Topic started by: Opethian on June 30, 2010, 12:03:31 PM

Title: Super CDROM sound issue
Post by: Opethian on June 30, 2010, 12:03:31 PM
I have a CGII + SCD that had level audio for about an hour until the all the sound went low almost to a whisper. I tested the SCD unit on the SGX and the sound is fine. I suspect the CGII is the culprit but I dont have an AC adaptor to test it alone. What could possible be the cause of the low audio? What kind of bit can I use to attack these 4 screws?
Title: Re: Core Grafx II sound issue
Post by: Opethian on July 04, 2010, 05:33:56 AM
SOLVED- Looks like the AV out on the SCD is the problem. Maybe it only works with a white PCE? or if I only had a white PCE I'd be screwed hehe.
Title: Re: Core Grafx II sound issue
Post by: rag-time4 on July 04, 2010, 11:18:11 AM
SOLVED- Looks like the AV out on the SCD is the problem. Maybe it only works with a white PCE? or if I only had a white PCE I'd be screwed hehe.
With my SCD + SuperGrafx setup I'm using the AV port of the SuperGrafx, not the SCD. How about you?
Title: Re: Core Grafx II sound issue
Post by: Opethian on July 05, 2010, 07:02:11 AM
Yea when I get my gamebit I'll inspect the SCD.
Title: Re: Core Grafx II sound issue
Post by: JapanTokei on July 06, 2010, 12:32:48 AM
Ope - I am guessing it's not your CoreGFX2 but the SCD attachment.  a few months ago I sold a duplicate bundle to a fella at Belgium on Ebay, and after he received it he claimed it was having the same problem as you.  I tried to troubleshoot the issue with him but ended up giving him 25 Euros + 3 free games since it was too expensive to have him ship it back, but from that experience (and choosing to trust he wasn't scamming me), I think the SCD add-ons has the sound issues due to caps as the Duos.  Although I don't have that issue with my other SCD addon unit, I have seem on YahooJP auctions a few loose SCD addons mentioned with the same issues (low sound). 

IF the AV port was the culprit then it's a nice simple prob ! 
Please do keep us posted after you pop it open and if you can confirm the Caps are the root cause... I'm interestd to confirm my theory and if that is the case then I need to pick up a few spare caps for future backup purposes too ... :)

Yea when I get my gamebit I'll inspect the SCD.
Title: Re: Core Grafx II sound issue
Post by: Opethian on July 07, 2010, 03:06:20 AM
Anyone know what size torx you need to open a SCD?
Title: Re: Super CDROM sound issue
Post by: BlueBMW on July 09, 2010, 02:15:06 PM
It seemed like my US Duo took a 4.5mm security bit.  Although it seemed a tad small so maybe 5mm is the correct size.  Not sure if its the same on the SCD though.
Title: Re: Super CDROM sound issue
Post by: Opethian on July 09, 2010, 05:09:24 PM
nah the Sysytems use a game bit to open. The SCDs have torx
(http://www.shop4tools.co.uk/acatalog/10125_stanley_torx_bit-sp.html)
Title: Re: Super CDROM sound issue
Post by: futurematt on July 27, 2010, 10:49:15 AM
Ope - I am guessing it's not your CoreGFX2 but the SCD attachment.  a few months ago I sold a duplicate bundle to a fella at Belgium on Ebay, and after he received it he claimed it was having the same problem as you.  I tried to troubleshoot the issue with him but ended up giving him 25 Euros + 3 free games since it was too expensive to have him ship it back, but from that experience (and choosing to trust he wasn't scamming me), I think the SCD add-ons has the sound issues due to caps as the Duos.  Although I don't have that issue with my other SCD addon unit, I have seem on YahooJP auctions a few loose SCD addons mentioned with the same issues (low sound). 

IF the AV port was the culprit then it's a nice simple prob ! 
Please do keep us posted after you pop it open and if you can confirm the Caps are the root cause... I'm interestd to confirm my theory and if that is the case then I need to pick up a few spare caps for future backup purposes too ... :)

Hey guys, I have exactly the same problem with my super CD Rom, the sound has gone WAY low on the AV out, by coincidence I just had it RGB Scart modded, but while the picture is way better, the sound is still the same!! Is it a case of replacing capacitors and if so, any clues as to where these are located on the board please>? Will be easy enought to pull them out and replace them when I know where they are.. Thanks.
Title: Re: Super CDROM sound issue
Post by: Opethian on July 27, 2010, 11:36:24 AM
I got mine open finally but I havent taken pics yet. The caps in my SCD dont look bowed up or leaky. I'll have to get a real closer look when I have time.
Title: Re: Super CDROM sound issue
Post by: pixeljunkie on January 21, 2011, 12:09:33 PM
I got mine open finally but I havent taken pics yet. The caps in my SCD dont look bowed up or leaky. I'll have to get a real closer look when I have time.

whatever came of this? I am having the exact same prob
Title: Re: Super CDROM sound issue
Post by: nat on January 21, 2011, 12:23:36 PM
I'm almost 100% sure it's the capacitors in the Super CD-ROM.
Title: Re: Super CDROM sound issue
Post by: Tablet on January 21, 2011, 09:38:11 PM
Yeah my SCD sound is 'crunchy' for the first few minutes until the caps warm up (well I assume the caps are warming up) But like others have said I run the audio out of my Core Crafx too.
Title: Re: Super CDROM sound issue
Post by: pixeljunkie on January 22, 2011, 05:33:48 AM
Just hoping someone who's had the problem and fixed it can say "yes, replace these caps" or "do this"

Kinda' nervous about just tearing the system up looking for things.
Title: Re: Super CDROM sound issue
Post by: BlueBMW on January 22, 2011, 02:21:42 PM
Replacing caps can never hurt unless you break something doing them.  And then you could rule out that its caps if it doesn't correct the problem.  If it is leaking caps... then the longer you wait to do em the worse the damage can be.
Title: Re: Super CDROM sound issue
Post by: Tablet on February 02, 2011, 09:30:53 AM
Aaaaaaawwwww man! My sound has gone from crunchy until warm to completely gone, does anyone still replace caps? I don't fancy my hand at doing it myself.
Title: Re: Super CDROM sound issue
Post by: Drumjay on February 28, 2011, 01:38:17 AM
I've just repaired a SCD Rom, and yes it was the capacitors. Every single one looked fine, no leaks, no corrosion at all, but after replacing 6 of them under the jumper board, right next to the AV port it was perfect! I did encounter one problem where the customer was using a power bridge connection for the SCD Rom and Core Grafx, The power hungry SCD Rom really needed that 12 Volts of power! It stopped the sound working fully when using this connection.

He then used separate connections for both units and found no problems after that. really should have taken pictures so I could have identified the caps for you all. But they are the same as usual 2 33uf and 3 100uf caps. Don't quote me on that, but I'm almost sure.
Title: Re: Super CDROM sound issue
Post by: BlueBMW on February 28, 2011, 03:40:54 AM
I can replace caps if you're still needing this done.  Let me know tablet!