Naomi 2 & Namco 256 super capacitor leak or possible leak

[vasilas432]

Hi guys,
I finally own a Naomi 2 with VF4E and I would like to know known issues for this Sega system to avoid unnecessary surprises. I had read somewhere that a big cap inside the system is prone to leak. Is this true? If yes what's the solution to this?
I also have read that there is an internal battery, does it need to be fresh or it's not necessary?

At this time I am not going to use a GD rom drive. I may buy a cart or two in the future if I discover any games I like.

Thanks in advance

[vasilas432]

I opened the Naomi 2 and located the super capacitor which btw had already leaked through its negative leg. I removed it and cleaned the place with isopropyl alcohol. Unfortunately the negative leg had its trace corrupted from acid and it couldn't leave the hole open after desoldering, for a new future capacitor to fit. I used a needle along with my soldering iron and somehow managed to restore it. I am not sure though if the negative trace is ok.

I can't power on the system because a Capcom I/O is still to come through mail so I can't tell if everything is working 100%. What is this capacitor needed for? I suppose as it was dead already that it didn't give anything to the system. Is it necessary to replace it or I can leave it empty?

The previous owner didn't care about the capacitor leakage even if it was easy to see, when not a cart in place and obviously had left it as is...
In case a replacement is necessary is this the one?
http://www.ebay.co.uk/itm/200700314720? ... EBIDX%3AIT

Many thanks

[bagheera369]

Can run fine without the Supercap. I have a Naomi2 that had the same issue...except I had more traces damaged. Chanelmanic over at the KLOV forums had to use some super fine filament wire and fix 4 or 5 traces, but now it works great. No supercap replacement in it.

If it boots, awesome. There maybe a few things some folks here would suggest to clean up that trace, and make absolutely certain nothing else is being eaten.
If it doesn't, its' time for trace repair, either by you, or anyone you know that can do it.

Best of luck!!!

Your board looks good though...definitely got that supercab hole, but didnt leak out to anything else it seems. you are very lucky. When they are stored vertically in the cab, it starts running down the board and kills all sorts of stuff.

[vasilas432]

Can run fine without the Supercap. I have a Naomi2 that had the same issue...except I had more traces damaged. Chanelmanic over at the KLOV forums had to use some super fine filament wire and fix 4 or 5 traces, but now it works great. No supercap replacement in it.

If it boots, awesome. There maybe a few things some folks here would suggest to clean up that trace, and make absolutely certain nothing else is being eaten.
If it doesn't, its' time for trace repair, either by you, or anyone you know that can do it.

Best of luck!!!

Your board looks good though...definitely got that supercab hole, but didnt leak out to anything else it seems. you are very lucky. When they are stored vertically in the cab, it starts running down the board and kills all sorts of stuff.

Thanks for your feedback!

I suppose system was stored horizontically and I m very curious why there is so little damage, the hole trace (which it won't be needed if no replacement) and it barely touched the R83 transistor or cap whatever it is. The sucker looks empty

How can I be sure the acid won't go further?

Thanks

[RMRM]

Make sure to clean the area with some water with baking soda on it to "cancel" any further acid spreading.

[vasilas432]

I have heard that but I didn't know how to make it. Baking soda is tha same we use sometimes in food?

Thank you

Make sure to clean the area with some water with baking soda on it to "cancel" any further acid spreading.

[vasilas432]

I have heard that but I didn't know how to make it. Baking soda is tha same white thing we use sometimes in food?

Thank you

Make sure to clean the area with some water with baking soda on it to "cancel" any further acid spreading.

[RMRM]

Yup, the same used to bake cakes. I don't think there is a "correct formula", i just add it to the water before it starts to get thick, then apply to the PCB with a brush. Let it rest for a couple minutes and in the end give it a good clean with water.

[vasilas432]

Yup, the same used to bake cakes. I don't think there is a "correct formula", i just add it to the water before it starts to get thick, then apply to the PCB with a brush. Let it rest for a couple minutes and in the end give it a good clean with water.

Great, I will do this on PGM too.

Thanks a lot

[Asayuki]

I opened the Naomi 2 and located the super capacitor which btw had already leaked through its negative leg. I removed it and cleaned the place with isopropyl alcohol. Unfortunately the negative leg had its trace corrupted from acid and it couldn't leave the hole open after desoldering, for a new future capacitor to fit. I used a needle along with my soldering iron and somehow managed to restore it. I am not sure though if the negative trace is ok.

The pads definitely look ripped off. I think I even see one of them still attached to the removed supercap. I think it can be easily fixed, but you will have to scrape some solder mask off for that.

[bagheera369]

Doesnt need to. Supercap is not needed for naomi to run and function correctly. As long as nothing continues to eat at that resistor, the board will be fine, once the baking soda thing is done.

I will keep that in mind for my future use too...makes sense...volcano science fair project and all....

[vasilas432]

I did a successful operation with baking soda yesterday. I put some soda without water at the point with the acid and then I dropped some water on the soda. It started to seethe and have some small bubbles by itself! I used a smal hard brush and made sure water and soda were mixed very good arround the sensitive pcb spot. Left it there for half an hour and then I washed it with water using a big soft painting brush.

I think super capacitor's both copper pads would be functional if I wanted to put a new one, but I won't if you say guys that it isn't needed. Nearby resistor is fine too. In general it doesn't look to have any damage other than the one ugly looking negative pad of the super capacitor. I only need to power the system up when the Capcom io arrives to confirm everything is functional.

Thanks for your help

[vasilas432]

I received my new Tekken 5 Dark Resurection Nanco 256 and turned it into pieces to clean all components inside and inspect it as I do with all my new pcbs. Everything was shiny and minty inside. While inspecting the small motherboard I noticed the usual suspect: a super capacitor with a reading of 5.5v on it. There is no leak and the capacitor looks like new, although it has never been changed according to its solder points.

What do we do in this case guys? Do we remove it or it is an entirely different story here in the 256?

[vasilas432]

Nothing on google got the Namco system super capacitor....I suppose it doesn't cause any issues.

BTW Namco system is all made in Japan while Naomi isn't...

[CelleGuy]

Hi everyone..i am a new user here. I have a Naomi2 that had the same issue...except I had more traces damaged. Chanelmanic over at the KLOV forums had to use some super fine filament wire and fix 4 or 5 traces, but now it works great. No supercap replacement in it.If it boots, awesome. There maybe a few things some folks here would suggest to clean up that trace, and make absolutely certain nothing else is being eaten.
If it doesn't, its' time for trace repair, either by you, or anyone you know that can do it.

https://www.7pcb.com/

[Asayuki]

I am not sure I completely understood what you meant, but you had better be careful in the repaired area. If you really have to do something around it, you had better ask Channelmaniac first.
As with regard to cleaning, he has probably already done it before reconnecting the traces. Unless you had new leakage, you had better leave the board as it is.

[bagheera369]

Hi everyone..i am a new user here. I have a Naomi2 that had the same issue...except I had more traces damaged. Chanelmanic over at the KLOV forums had to use some super fine filament wire and fix 4 or 5 traces, but now it works great. No supercap replacement in it.If it boots, awesome. There maybe a few things some folks here would suggest to clean up that trace, and make absolutely certain nothing else is being eaten.
If it doesn't, its' time for trace repair, either by you, or anyone you know that can do it.

CelleGuy....why would you just exact copy my whole post from earlier, and then drop it here again????? O.o

[vasilas432]

Yesterday I finally got the Capcom I/O and powered on Naomi 2 successfully. I put a fresh battery but left it without a super capacitor. Holds clock settings fine.

Note: Naomi 2 in order not to freeze needs a stable 5v. Had to adjust my PSU at a 5.30 without a PCB connected.

If I keep this voltage setting I don't know how healthy is for other pcbs to work around 5,15 volts though..

[Asayuki]

Typical TTL ICs have a recommended operating voltage tolerance of +/- 5%. Remember however that your power supply also has a tolerance. What is 5.15V today can be 5.20V tomorrow.
Also check that your PSU is able to deliver the required current. Power cabling gauge also needs to be adequate to the required current.

[vasilas432]

Here is a picture of my set up. While on CPS3 voltage reading on jamma is 5.07. Is this real voltage on the pcb?