Saturn repair questions

This is exactly the same my Saturn did after installing the multi BIOS chip...

So I taking a guess here, maybe the BIOS is bad?

 

I have not replaced the bios yet.

Im experienced enough not to add variables into the mix while fault finding.

However, if all else fails - I will try replacing the original bios with a replacement - in the unlikely event the original has died somehow.

Druid - the leg actually came off, I have dremelled the chip and fashioned a replacement leg. there is no bridging between pins and the replacement "pin" is 100% fine.

There is no problem with the soldering, I can assure you.


And I dont think I am getting audio.... again, lack of owning a saturn before is working against me... is there a startup sound if you boot without a disk? or some ambient menu noise?

 

That's what I was trying to say, looks like a dead original BIOS... maybe you should replace it with a new one.

Yes there is a startup sound, don't know right now if it comes before entering the settings screen though. But you get a sound when you move around the settings with the gamepad.

 

it could be a number of things before the original bios - but yes, it is something I have thought of.

At this stage id like to rule out the PSU and hear comments from people who have repaired faults with their consoles.

Im reluctant to switch the original just yet - mostly because of the issues you had - I dont want to swap the bios then there actually be a compatibility issue which will hinder the repair.

edit:

just a correction now I am home... its a VA9 not VA7

 

Ok, just checked voltages on the PSU.

Im getting...

while in the console:
GND | GND | 5.5V | 5.5V | 12.2V

while out of the console

GND | GND | 5.5V | 5.5V | 9.2V

is that normal?? because it doesnt sound it to me... (but I have nothing to compare to)


Edit:

oops, double post - sorry.

 

Last time I checked my working EUR "Model 2" PSU it had +5V and +9V. The values should be printed on the PSU or mainboard.
Unfortunately I can't test it further to confirm you readings because it is built in in my Skeleton Saturn and that doesn't use the +9V rail.

 

Found PSU labelling. says 5.2v and 12v

 

x

 

Ah, sounds like the higher voltage pin is just used for the scart auto switching

 

Yes, that makes sense, when "fixing" the JAP A/V port for EUR SCART cables I was missing the 9V pin and had to use an EUR PSU.

And it explains why your TV is switching to SCART.
So, that leaves you with a working PSU and perhaps a dead board or bios. And maybe the broken leg...

 

its definitely not the broken leg. I have been soldering for YEARS and have like 2k worth of soldering equipment at home for hobby use.

I also did about 900 million D2B Wii drives with cut legs.

So, its looking like something on the board...

 

x

 

http://www.youtube.com/watch?v=hpPHFIed7nE

If the Saturn is 100% able to properly detect and work with the optical assembly the above will appear. If it is not it skips over it displaying a single splash screen and dropping to the sounds you hear in that video after it drops to the BIOS menu. In other words: you should hear SOMETHING.

IMO what you've got there is something a bit more low level a problem which I see you're coming to the conclusion of as well. I believe there are Saturn schematics out there but I can't for the life of me recall where I've seen them.

 

It certainly looks that way.

I think my plan will have to be:

1. Resolder all the chips to rule out a bad joint somewhere.
2. Then replace the bios with the hacked one.
3. Then bathe the board.
4. Then reflow the whole board.
5. Then throw it in the parts box

In that order.

I have another working Saturn coming to be in a couple of weeks for free anyway. But it would be nice to get this one working as well.

 

I could have a look at my Saturn parts box, there must be some spare working EU/Model2 mainboards in it if you are interested.

 

Depends on price really. I can buy a whole working console for like £30 including shipping.

Let me know what you have in mind. Also, if you have any broken boards from the bios adventure (bad pads etc) id be willing to use those too

 

Correction:

They're for a later JAPANESE model (White Saturn) that happened to be dumped in Brazil when SEGA moved on to the Dreamcast.

 

x

 

More info!

Apparently this Saturn used to boot to the splash screen and then hang/lock up. But when I got it, I didnt even get that.

Bad joint on the ram maybe? or maybe bad ram chip?