The bad battery thread

Hairy Otter

New Challenger
Joined
Aug 11, 2012
Posts
53
I contacted the seller yesterday to work something out; I'd rather just fix it and be done.
but what's a fair price for a board with this kind of damage?
Is the board running elseways, or has it other issues as well?
I've had boards that looked worse, but run just fine after cleaning and doing a battery mod.

I hunt down and bridge broken track and re-flow ugly looking legs (like on the NEO-ZMC2 in your picture) with plenty of "no clean" flux, and clean the whole area with rubbing alcohol. I don't know if this is the best way to do this, but my first repair three years ago is stil up and running and I hope it will be for a long time.
If anybody has a better way of cleaning I'm happy to hear it.
 

xsq

Thou Shalt Not, Question Rot.,
Joined
Jan 17, 2013
Posts
7,414
does it matter what kind of vinegar I use? I don't have any regular white.
DON'T USE VINEGAR. [I know I posted about doing just that before - but I know better now.]

Do as follows:
1. Try to clean the spot as much as you can with a dry cloth and then some rubbing alcohol.
2. Mix baking soda with some water to a paste and apply it to the damaged parts with a toothbrush.
3. Let it sit for a short while (20-30 Min.).
4. Clean with distilled/demineralized water.
5. Dry the board. (Hand-dry with a clean and soft cotton cloth. Easiest way to make sure the board is really really dry is heating your oven to ca. 70ーC, then turn it off (!) and put the PCB inside over night.)

Here's why: Mixing an acid (vinegar) with a base (leakage) could lead to a chemical reaction that will further damage your board. Also the proportions of battery leak to vinegar would have to be perfect to really neutralize the leakage and not leave some of the vinegar on the board that will eat through the metal even faster. Backing soda (sodium bicarbonate) is amphoteric, so it will neutralize bases and acids.

Thanks to the people schooling me on this. Read further here and here.



Is the board running elseways, or has it other issues as well?
I've had boards that looked worse, but run just fine after cleaning and doing a battery mod.
this.
 

bartre

Haomaru's Blade Shiner
10 Year Member
Joined
Oct 27, 2009
Posts
681
Is the board running elseways, or has it other issues as well?
I've had boards that looked worse, but run just fine after cleaning and doing a battery mod.

I hunt down and bridge broken track and re-flow ugly looking legs (like on the NEO-ZMC2 in your picture) with plenty of "no clean" flux, and clean the whole area with rubbing alcohol. I don't know if this is the best way to do this, but my first repair three years ago is stil up and running and I hope it will be for a long time.
If anybody has a better way of cleaning I'm happy to hear it.

Well there's some graphical fuckery.
But as far as I know, that could also be caused by a loose/dirty cart slot.

To repair the traces, should I run wires, or is it better to just scrape the mask and flow some solder?
 

xsq

Thou Shalt Not, Question Rot.,
Joined
Jan 17, 2013
Posts
7,414
To repair the traces, should I run wires, or is it better to just scrape the mask and flow some solder?
I would run wires and connect the components directly (and not try to just bridge the broken part of the trace(s)). Should be less work and surer to succeed.
 

pepelegit

Pleasure Goal
Joined
Aug 15, 2009
Posts
146
Man, it's good to be back, and what a fantastic thread. I think I completely missed this one when I was previously active on here, but as I'm preparing to spend more time with the Neo, I got to thinking I should look into tidying it up a bit (some slots work better than others, but it mostly just needs a good cleaning). Now I know what I'll be checking on first!
 
Joined
Dec 20, 2017
Posts
38
DON'T USE VINEGAR. [I know I posted about doing just that before - but I know better now.]

Do as follows:
1. Try to clean the spot as much as you can with a dry cloth and then some rubbing alcohol.
2. Mix baking soda with some water to a paste and apply it to the damaged parts with a toothbrush.
3. Let it sit for a short while (20-30 Min.).
4. Clean with distilled/demineralized water.
5. Dry the board. (Hand-dry with a clean and soft cotton cloth. Easiest way to make sure the board is really really dry is heating your oven to ca. 70ーC, then turn it off (!) and put the PCB inside over night.)

Here's why: Mixing an acid (vinegar) with a base (leakage) could lead to a chemical reaction that will further damage your board. Also the proportions of battery leak to vinegar would have to be perfect to really neutralize the leakage and not leave some of the vinegar on the board that will eat through the metal even faster. Backing soda (sodium bicarbonate) is amphoteric, so it will neutralize bases and acids.

Thanks to the people schooling me on this. Read further here and here.




this.

thanks for this xsq. just starting to clean for the first time and this helps alot!
 

bwi

,
20 Year Member
Joined
Dec 15, 2000
Posts
460
can anyone tell me if i just have to remove the 470 resistor on this board or is it one where you have to remove and reuse the 1S1588 diode as well.
I've been on JNX and no luck also i found a video with a very similar board https://www.youtube.com/watch?v=LnDsyL5xIEc

I've also took a picture just to show what i have

20180127_122155.jpg
 

gamelife00

Rugal's Thug
Joined
Jan 3, 2018
Posts
91
Hi all,i have an MV-1C board with the vertical battery Holder. How easy are these ones to swap out, it's a coin type. So is it a case of just swapping for a new one? If so what battery would be suitable. Thanks
 

MobiusStripTech

Mr. Big's Thug
Joined
Dec 4, 2017
Posts
201
Hi all,i have an MV-1C board with the vertical battery Holder. How easy are these ones to swap out, it's a coin type. So is it a case of just swapping for a new one? If so what battery would be suitable. Thanks

A lot of people opt to remove the charging circuit and switch to a standard CR2032 and a basic coin cell socket. I opted for an SMD coin cell socket and to still use the LR2032 rechargeable battery personally.
 

8bitForLife

Crazed MVS Addict
Joined
Oct 8, 2013
Posts
134
A lot of people opt to remove the charging circuit and switch to a standard CR2032 and a basic coin cell socket. I opted for an SMD coin cell socket and to still use the LR2032 rechargeable battery personally.
Would doing this be as easy as replacing batteries in snes carts or putting a socket in a dreamcast for easy battery removal?
 

MobiusStripTech

Mr. Big's Thug
Joined
Dec 4, 2017
Posts
201
Essentially. The level of difficulty just depends on the socket you intend to install and your skills. The MV1C has a non-standard pin layout which basically means you probably won't find a direct fit socket. In most cases you can attach a component lead to the socket pins and connect those to the original solder points or even alternative points.

Overall it really isn't difficult to do this though.
 

nerger

n00b
Joined
Mar 27, 2018
Posts
7
I have a MVS4FS board that had a dead battery.

I removed it and replaced it with a CR2032 holder, i also followed HairyOtters guide to disable the charging circuit

mv4fs-battery-mod.jpg


All seems to be working, but when I use a UniBios the games all crash on the screen that shows you the moves. Anyone any ideas on what could be causing it or how I can debug it?
 

MobiusStripTech

Mr. Big's Thug
Joined
Dec 4, 2017
Posts
201
I have a MVS4FS board that had a dead battery.

I removed it and replaced it with a CR2032 holder, i also followed HairyOtters guide to disable the charging circuit

mv4fs-battery-mod.jpg


All seems to be working, but when I use a UniBios the games all crash on the screen that shows you the moves. Anyone any ideas on what could be causing it or how I can debug it?

Does it still crash with a regular bios? Does it crash if you remove the battery?
 

nerger

n00b
Joined
Mar 27, 2018
Posts
7
Does it still crash with a regular bios? Does it crash if you remove the battery?

Doesn't crash with the regular bios installed, only happens with UniBios

I am not with the board currently but will check if it still happens with the battery removed and report back
 

nerger

n00b
Joined
Mar 27, 2018
Posts
7
Reviving this thread from the dead! I have tried it without the battery installed and all works well.
 

Hairy Otter

New Challenger
Joined
Aug 11, 2012
Posts
53
Reviving this thread from the dead! I have tried it without the battery installed and all works well.
This thread is still useful so the revive is permitted I think.
The board will work fine without the battery, only it can't keep its RAM operational during power off.
First it doesn't keep track of game time. This is for most of us not that important.
The other thing it doesn't "remember" the soft DIP's. These can influence the difficulty level, the continu option, demo sound etc...
These DIP settings are game related.
Also Hi-scores are stored in this RAM.
If you don't need these options you are fine without the battery, else you can put in a 2032 holder (don't forget to disable the loading circuit) or a rechargeable battery.
 

nerger

n00b
Joined
Mar 27, 2018
Posts
7
This thread is still useful so the revive is permitted I think.
The board will work fine without the battery, only it can't keep its RAM operational during power off.
First it doesn't keep track of game time. This is for most of us not that important.
The other thing it doesn't "remember" the soft DIP's. These can influence the difficulty level, the continu option, demo sound etc...
These DIP settings are game related.
Also Hi-scores are stored in this RAM.
If you don't need these options you are fine without the battery, else you can put in a 2032 holder (don't forget to disable the loading circuit) or a rechargeable battery.

Maybe some crossed wires here!

I followed your guide on disabling the charging circuit and have installed a 2032 holder. But with a UniBios installed and a battery then it crashes on the game instructions screen.

It seems that something in the way the charging circuit is disabled does not agree with the unibios.

Do you have unibios in your board?
 

nerger

n00b
Joined
Mar 27, 2018
Posts
7
Maybe some crossed wires here!

I followed your guide on disabling the charging circuit and have installed a 2032 holder. But with a UniBios installed and a battery then it crashes on the game instructions screen.

It seems that something in the way the charging circuit is disabled does not agree with the unibios.

Do you have unibios in your board?

I have just rechecked my soldering and tidied things up, on reassembling all seems to be working correctly with a battery installed and the unibios now

If I take out the battery and measure across the terminals then I get 0.3v when the board is powered up, does sound like the charging curcuit is disabled correctly?
 

Hairy Otter

New Challenger
Joined
Aug 11, 2012
Posts
53
If I take out the battery and measure across the terminals then I get 0.3v when the board is powered up, does sound like the charging curcuit is disabled correctly?

I just measured my board, I only have 0.03v even if it is turned off. But I have this on my meter if it isn't connected as well.
Can you put up a picture from your board, the one in your post looks a lot like mine. Both front and back please, the .3v isn't that much but I think the battery doesn't like this.

btw. sorry for skipping your previous posts.
 

nerger

n00b
Joined
Mar 27, 2018
Posts
7
Have just done some more testing. The issue seems to be coming from the the 470u capacitor.

It is sending 0.3v to the battery, after the board is switched off it takes ages to discharge so is still measuing 0.3v even with power off.

If you short the cap after turning the board off then you get 0v at the battery.

I have not got a working camera with me at the minute so I can't take any pics, but wiring is exactly as your example.

I just measured my board, I only have 0.03v even if it is turned off. But I have this on my meter if it isn't connected as well.
Can you put up a picture from your board, the one in your post looks a lot like mine. Both front and back please, the .3v isn't that much but I think the battery doesn't like this.

btw. sorry for skipping your previous posts.
 

nerger

n00b
Joined
Mar 27, 2018
Posts
7
Created an overlay image of the 2 sides of an MV4FS board, though it might help make things clearer...

merged.jpg
 

Hairy Otter

New Challenger
Joined
Aug 11, 2012
Posts
53
Created an overlay image of the 2 sides of an MV4FS board, though it might help make things clearer...
this image is not made from your board, I think. The battery is removed but the charging circuit is still there.

If the voltage is coming from the capacitor it seems to me the diode isn't doing its job. Did you exchange the zener with the diode?
 

Whippy

Banned
Joined
Apr 1, 2019
Posts
153
This is somewhat related, and my question did not require a separate thread.

I have a mv-1c that I got with the battery removed. I was able to use a LIR2032 & battery holder to maintain the clock/region. The long and short of it was that the battery either failed, or due to me putting it in upside down it died (negative to positive/I got wires crossed). I don't know which, or how to test, but I figured I burned up something on the board (I am no electronics guy). Today I got a ML2032, and installed it and everything seems good.

My question: Does the MVS recharge a dead battery, or is this what my problem was? Is there another problem I should be looking for?
 

Hairy Otter

New Challenger
Joined
Aug 11, 2012
Posts
53
This is somewhat related, and my question did not require a separate thread.

I have a mv-1c that I got with the battery removed. I was able to use a LIR2032 & battery holder to maintain the clock/region. The long and short of it was that the battery either failed, or due to me putting it in upside down it died (negative to positive/I got wires crossed). I don't know which, or how to test, but I figured I burned up something on the board (I am no electronics guy). Today I got a ML2032, and installed it and everything seems good.

My question: Does the MVS recharge a dead battery, or is this what my problem was? Is there another problem I should be looking for?
Your problem is a bit confusing.
Answer on your question, MVS does charge its battery, but by dead I hope you mean empty. There can be several problems you can look for:
First, an mv-1c seems to consume a lot of battery power when not powered.
Second, all MVS boards are designed to be powered on for more than half a day, every day. The battery only needs to hold for the night. A rechargeable battery kan take up to 8 hours. I don't know what battery is used on an original mv-1c board, but a LIR2032 is a li-ion battery. Those things need a special loading circuit. They can explode when charged wrong.
 

Whippy

Banned
Joined
Apr 1, 2019
Posts
153
Your problem is a bit confusing.
Answer on your question, MVS does charge its battery, but by dead I hope you mean empty. There can be several problems you can look for:
First, an mv-1c seems to consume a lot of battery power when not powered.
Second, all MVS boards are designed to be powered on for more than half a day, every day. The battery only needs to hold for the night. A rechargeable battery kan take up to 8 hours. I don't know what battery is used on an original mv-1c board, but a LIR2032 is a li-ion battery. Those things need a special loading circuit. They can explode when charged wrong.

By dead, I mean that the battery is reading 0.0 volts. The LIR2032 was purchased with advice from this forum (possibly this thread/I followed an ebay link) where there was a reference to the dreamcast battery replacement mod....I got the LIR2032 & battery holder. I would have to look, but I think it has been nearly 2 months since I added the LIR2032. At one point last week I left the unit on overnight, and it didn't seem to charge, but I didn't test it aside from waking up, turning the system off, than back on only to find that it didn't save my region/time. Perhaps it never charged, and was improper for the system?

I am also realistic that the battery does next to nothing on the 1c board, as it doesn't save high scores that I can tell.

The battery I replaced it with was a ML2032, and everything seems to be working again when it comes to time/date/region. Which brings me to another question. Is the ML2032 the proper rechargeable battery to use in a 1c with the charging circuitry still in place?

Thanks again for your response!
 
Last edited:
Top