no left audio with SNES

Shadow_Zero · December 01, 2006, 04:44:49 PM

One of my SNES' doesn't have left audio. I tried this http://www.mmmonkey.co.uk/console/nintendo/snes-glitches.htm to ressolve it, but with no luck. Do I bend the pins lightly? Or can I press them forward pretty (relatively) much?

Anyone else any ideas how I can fix this?
It's not the cable or the tv in any case, since I tried the machine with different cables and tv's.

blackevilweredragon · December 01, 2006, 05:11:10 PM

that fix has NOTHING to do with the audio....

Check the AV connection on the back... open up the SNES, makes sure theres no cold solder joints.. and if you have to, unscrew the SPC, and re-seat it..

Shadow_Zero · December 04, 2006, 01:38:15 AM

Quote
If your SNES or Super Famicom has distorted or even missing sound and/or graphics then you may be able to fix it by simply adjusting the contacts of the cartridge connector.

I read that, so it made me believe

I'll check on the SPC, not familiar with that, but my SNES is wide open at the moment.

GZeus · December 04, 2006, 04:13:37 PM

I think by 'missing sound' they mean 'missing instruments or sound effects.

Shadow_Zero · December 04, 2006, 05:51:06 PM

Ah, alright!

I haven't been able to identify the SPC. Where is it located exactly?

blackevilweredragon · December 05, 2006, 03:28:09 PM

QuoteAh, alright!

I haven't been able to identify the SPC. Where is it located exactly?

it's the big silver box at the back right...

Shadow_Zero · December 05, 2006, 04:24:40 PM

I got a hunch it was that, but I can't seem to get it fully loose...
Perhaps I should make some pics

(though tips are welcome as well of course

)

blackevilweredragon · December 05, 2006, 05:40:17 PM

QuoteI got a hunch it was that, but I can't seem to get it fully loose...
Perhaps I should make some pics
(though tips are welcome as well of course )

i believe it is held down by two screws.. (might be 4) at the corners..

once those are gone, it should lift right out.. once it's out, clean the contacts CAREFULLY on it.. then reseat it back onto the logic board for the SNES..

while the SNES communicates by parallel data to the I/O lines on the SPC, the SPC sends back analog audio on the same bus connector, which goes right to the audio out pins on the AV multiout connector..

Shadow_Zero · December 05, 2006, 07:55:10 PM

Thanks for the input.
I'll try it out when I get back from work

What's the best way to clean this?
(which tool? cleaning liquid or not?)

blackevilweredragon · December 06, 2006, 01:45:00 AM

i personally use a non-static cotton swab, with some rubbing alcohol on the tip, and once cleaned, let it dry.. then try reconnecting it..

actually, you can try reseating it without cleaning.. sometimes even that can rub off any crud on it..

Shadow_Zero · December 18, 2006, 05:51:57 AM

Some pics:
http://rguichelaar.dyndns.org/games/snes/snes_pcb1.jpg
http://rguichelaar.dyndns.org/games/snes/snes_pcb2.jpg
http://rguichelaar.dyndns.org/games/snes/snes_pcb3.jpg

I can't seem to get the pvc part off from the pcb (so the part where the av connector is; right-down first pic).
Do I have to get that off? It seems to be attached (soldered?) to the ac connection or something like that.

Other than that, where can I focus on in order to fix the audio?

blackevilweredragon · December 18, 2006, 05:57:04 AM

oh, my, god.. what did that thing go through??

was something spilt all over this thing?

Shadow_Zero · December 18, 2006, 06:06:24 AM

Quoteoh, my, god.. what did that thing go through??

was something spilt all over this thing?

Explain yourself?

And... I have no idea, I have it like, for over 13 years

(and it never has been opened)

blackevilweredragon · December 18, 2006, 06:07:26 AM

Quote
Quoteoh, my, god.. what did that thing go through??

was something spilt all over this thing?
Explain yourself?

And... I have no idea, I have it like, for 13 years

well, i see a lot of brown stuff on the circuit.. i can't tell if it's Flux or Coffee.

Shadow_Zero · December 18, 2006, 06:13:39 AM

I don't know what flux is. Can it be some sort of glue?
It surely isn't coffee...

But, how do I get the pvc off the board so I can take off the SPC?
And some other points of attention perhaps?

blackevilweredragon · December 18, 2006, 06:15:15 AM

SPC just detaches with screws.. you don't need to take the metal off of it... just reseat the thing in it's socket, then try again...

Shadow_Zero · December 18, 2006, 06:45:30 AM

Ok, so I don't need to take the metal off from the board (which doesn't seem to be possible).
I did some cleaning, but can you point out what/where exactly I should clean with the cotton-swab?

And I don't really notice a socket which holds the SPC, do you mean the RF-out which is attached to the whole block?

blackevilweredragon · December 18, 2006, 06:57:25 AM

QuoteOk, so I don't need to take the metal off from the board (which doesn't seem to be possible).
I did some cleaning, but can you point out what/where exactly I should clean with the cotton-swab?

And I don't really notice a socket which holds the SPC, do you mean the RF-out which is attached to the whole block?

when the SPC comes off, there's pins that attach to the motherboard (it's a socket)...

I believe it's black colored (it was that on mine)

GZeus · December 18, 2006, 12:53:19 PM

That's either flux or just some resin.
I see that on alot of mass-produced PCBs.
Generally lower-end stuff from about 10-15 years ago, but sometimes better stuff.

NeWmAn · December 19, 2006, 03:17:21 AM

His audio chips are soldered on the mainboard, he doesn't have the socketed audio module.
Moreover looking at one of the photos there seem to be some problems:

blackevilweredragon · December 19, 2006, 04:56:10 AM

i thought all SNES model 1's had socketed SPC modules..

Shadow_Zero · December 19, 2006, 07:18:03 AM

It's a PAL snes, dunno if that differs with the US/JAP SNES/Super Famicom...?

ニユ－マ: you think those parts you highlighted are the problem? Any way to fix that? I did some cleaning, but I still need to connect and test.

blackevilweredragon · December 19, 2006, 07:42:32 AM

I think they were all the same, but I could be wrong..

I can't tell if that weird marking is mold, or not. it looks odd, and i can't believe i missed that...

NFG · December 19, 2006, 07:42:50 AM

Quotei thought all SNES model 1's had socketed SPC modules..

Not at all. In my experience slightly fewer than half have socketed modules.

blackevilweredragon · December 19, 2006, 07:56:04 AM

hmm, ok, thanks for the correction.. i've always ran into socketed ones here... (and prefer those too, cause they can be hacked to run on a PC)

NeWmAn · December 19, 2006, 09:39:08 AM

Quote
ニユ－マ: you think those parts you highlighted are the problem? Any way to fix that? I did some cleaning, but I still need to connect and test.

Can't tell from the photo, but the traces have a nasty color, maybe there's rust or the traces are burnt?
The part marked in the lower right seems that is peeling off...

Btw I had 3 PAL and one US SNES and none of them had the separated audio module.

Shadow_Zero · December 19, 2006, 05:29:51 PM

It does seem like a bit of rust yeah (or could be burnt, but dunno why/how it could've been burnt).

Btw, what IS the audio chip then on my board?
Can the "rusted" parts be the problem of the left channel audio not working?
Is that fixable?

blackevilweredragon · December 19, 2006, 05:48:39 PM

the audio chip would say Sony SPC700...

that component has two electrolytic capacitors.. while i don't know their functions, they could possibly be for the audio.. left and right...

NeWmAn · December 20, 2006, 03:36:01 AM

Quote
Btw, what IS the audio chip then on my board?

Look at your first photo:
http://ourworld.compuserve.nl/renguich/img/snes_pcb1.jpg

The 2 bigger ICs on the left, S-DSP and S-SMP with Sony and Nintendo © are the audio chips, the other 2 are the audio rams.

Quote
Can the "rusted" parts be the problem of the left channel audio not working?
Is that fixable?

It may be just an optical illusion in that photo, a new (better, more in focus) photo of the rusted traces may help us diagnose the problem!
If you have a multimeter you should check continuity in those traces, it's a 2 minutes job.

Shadow_Zero · December 20, 2006, 08:16:17 AM

Unfortunately I don't have a multimeter.
It's hard to get sharp pics.
Here's another two:
http://rguichelaar.dyndns.org/games/snes/snes_pcb4.jpg
http://rguichelaar.dyndns.org/games/snes/snes_pcb5.jpg

I'll try to get something better/sharper.

blackevilweredragon · December 20, 2006, 08:35:45 AM

look for a Macro button on your camera.. usually marked with a flower..

Shadow_Zero · December 20, 2006, 08:58:58 AM

Yeah, I'm using that. But I have to hold the camera VERY still, which is hard with bare hands

Some additional ones:

http://rguichelaar.dyndns.org/games/snes/snes_pcb6.jpg
http://rguichelaar.dyndns.org/games/snes/snes_pcb7.jpg
http://rguichelaar.dyndns.org/games/snes/snes_pcb8.jpg
http://rguichelaar.dyndns.org/games/snes/snes_pcb9.jpg

NeWmAn · December 21, 2006, 04:30:18 AM

It's strange to see so much flux residue around the big ICs, it looks as if those were hand soldered :blink:

Anyway, if you can't take a better photo try to clean the "rusted" traces (alcohol, acetone, paint thinner will work) and see if the trace below is still there.

Shadow_Zero · December 21, 2006, 07:48:32 AM

I did some cleaning with alcohol, but that didn't seem to help.
How thoroughly should I clean it?
(like, using a lot of alcohol or not, pressing hard with the cotton swab or not?)

NeWmAn · December 21, 2006, 08:30:31 AM

Too much alcohol won't accomplish nothing, just a few drops where is the dirt, then rub with the cotton swab (press hard, you can't damage the circuit with it).
If alcohol is not enough and you don't have acetone or thinner you can try with a pencil eraser, but don't press too hard and be careful to not bend the capacitors that are close.

Can you tell if it's dirt, rust, paint or what? Can you see if the trace below is intact?

blackevilweredragon · December 21, 2006, 08:33:49 AM

just had a thought.. got a video camera, with an eye piece that comes off? hold that up to the cameras lens, that will produce the BEST macro shot you can possibly get.. Just, make sure you have extra light in the area..

Shadow_Zero · December 26, 2006, 06:51:16 AM

Nope, don't have a camera with an eye-piece that comes off.
It's "just" a 5 megapixel Kodak.

I tried to make some more/better pics:
http://rguichelaar.dyndns.org/games/snes/snes_pcb10.jpg
http://rguichelaar.dyndns.org/games/snes/snes_pcb11.jpg
http://rguichelaar.dyndns.org/games/snes/snes_pcb12.jpg
http://rguichelaar.dyndns.org/games/snes/snes_pcb13.jpg
http://rguichelaar.dyndns.org/games/snes/snes_pcb14.jpg
http://rguichelaar.dyndns.org/games/snes/snes_pcb15.jpg

ニユ－マ:
What exactly do you mean with "see if the trace below is intact" ?

blackevilweredragon · December 26, 2006, 07:08:50 AM

it almost looks like a burn..

NeWmAn · December 26, 2006, 09:36:19 AM

Quoteニユ－マ:
What exactly do you mean with "see if the trace below is intact" ?

I meant: try to see if if the circuit trace below the dirt/rust was still capable of conducting electricity (was still in one piece).

Anyway I agree with blackevilweredragon, if you have tried with the pencil and it's still brownish then it's probably burnt.
I suggest you to get a multimeter and check continuity in those burnt traces, if you find that some are interrupted you should repair them with some pieces of wire.

This page may help you in figuring out how to repair a broken trace:

http://machrone.home.comcast.net/bjr/mistakes.htm

NOTE:
A circuit board burnt is usually not a good sign, but I cannot assure you that your missing audio channel is related to this problem.

Shadow_Zero · December 26, 2006, 10:36:47 AM

http://rguichelaar.dyndns.org/games/snes/snes_pcb12.jpg is the underside of the board. Hard for me to tell if it's all still connected, but I don't see anything out of the ordinary.

I have the idea that the black parts can be peeled off with a knife, but I didn't try too hard. No luck with the alcohol or pencil eraser.

I should take it to work, I'm sure there are a few guys there with a multimeter

News:

no left audio with SNES