Hardware GCN Question about GameCube laser

[ThaKarra]

Hi all,

Yesterday I received a boxed Nintendo GameCube (DOL-101) console.

My main goal here was to install a picoboot modchip inside, but before any of that I wanted to do some initial testing.

I inserted a disc and it done the famous 'no spin' and straight to the dashboard. So I took it apart, adjusted the laser POT to about 30ohms and tried it again. Worked perfectly. I tried about 3-4 different games and it booted every time.

However I thought that 30ohms might have been a little low so I went back and adjusted it to around 60ohms. I took it back over to the TV and gave it another try. It was still "working", but this time it was a little hit or miss. It failed to boot maybe once every five attempts.

So I left it alone and went on to install the Picoboot mod, thinking I could just tweak the laser later... because at least it was booting discs now...

Picoboot installation done. I went back over to the TV, everything was working correctly, SWISS booted fine etc.. Went to try and boot a game and I got the dreaded red error "The game disc could not be read. Please read the Nintendo GameCube instruction booklet for more information.".

I quickly took it apart and tried adjusting the POT back to the original 30ohms, but nothing. - From this point I've not been able to get a single disc to boot. It just displays the same error every time. I've tried cleaning the laser with a cue tip and alcohol as well.

I should have left it alone at 30ohms when it was working flawlessly. --

Does anyone know what might have caused this or have any solutions to fixing it?

 

[SylverReZ]

tl;dr

https://www.gc-forever.com/wiki/index.php?title=Laser_Tuning

 

[The Real Jdbye]

Hi all,

Yesterday I received a boxed Nintendo GameCube (DOL-101) console.

My main goal here was to install a picoboot modchip inside, but before any of that I wanted to do some initial testing.

I inserted a disc and it done the famous 'no spin' and straight to the dashboard. So I took it apart, adjusted the laser POT to about 30ohms and tried it again. Worked perfectly. I tried about 3-4 different games and it booted every time.

However I thought that 30ohms might have been a little low so I went back and adjusted it to around 60ohms. I took it back over to the TV and gave it another try. It was still "working", but this time it was a little hit or miss. It failed to boot maybe once every five attempts.

So I left it alone and went on to install the Picoboot mod, thinking I could just tweak the laser later... because at least it was booting discs now...

Picoboot installation done. I went back over to the TV, everything was working correctly, SWISS booted fine etc.. Went to try and boot a game and I got the dreaded red error "The game disc could not be read. Please read the Nintendo GameCube instruction booklet for more information.".

I quickly took it apart and tried adjusting the POT back to the original 30ohms, but nothing. - From this point I've not been able to get a single disc to boot. It just displays the same error every time. I've tried cleaning the laser with a cue tip and alcohol as well.

I should have left it alone at 30ohms when it was working flawlessly. --

Does anyone know what might have caused this or have any solutions to fixing it?

30 ohm might have been too low and you might've damaged the laser.
Anyway, pot tweaks are only a temporary fix. When a laser is worn and you lower the resistance to compensate, that accelerates the wear further. Eventually the laser is just gonna die completely anyway.

 

[ThaKarra]

30 ohm might have been too low and you might've damaged the laser.
Anyway, pot tweaks are only a temporary fix. When a laser is worn and you lower the resistance to compensate, that accelerates the wear further. Eventually the laser is just gonna die completely anyway.

Awesome! I just wanted to confirm that as the issue before I went out and purchased a replacement laser. I read other things about the drive possibly needing a recap etc.

Another question. If I do go and purchase a new laser, what should I set the POT too, since it's currently sitting on 30ohms?

 

[The Real Jdbye]

Awesome! I just wanted to confirm that as the issue before I went out and purchased a replacement laser. I read other things about the drive possibly needing a recap etc.

Another question. If I do go and purchase a new laser, what should I set the POT too, since it's currently sitting on 30ohms?

Recapping is not a bad idea, capacitors are dirt cheap if you buy big packs of them.
The link posted above has some factory values, I would start at the higher end of the range and go with the highest resistance that results in reliable reading (to minimize wear)

 

[ThaKarra]

Recapping is not a bad idea, capacitors are dirt cheap if you buy big packs of them.
The link posted above has some factory values, I would start at the higher end of the range and go with the highest resistance that results in reliable reading (to minimize wear)

Awesome! Thanks for your help

 

[ThaKarra]

I'm a dumbass hahaha... For anyone who wants an update...

The reason the drive wasn't working after I installed the Picoboot mod was because at the time of installing, I also bridged the R6 points to turn the console into a NTSC-U unit. The reason I was getting a disk read error was because I was still testing the drive with NTSC-J games...