my naomi board is out of servece? helllllllllllllp

OldFoo · Post by **OldFoo** » Fri Feb 06, 2009 12:32 am

1 year every thing is ok i use naomi 1 mother board with the game of zombe revenge i use capcom converter i use my normal power suply i'm not using 3.3 power supply the problem is when i turn on the cabinet nothing happend or shown on the screen i tried to incese the voltage but the same problem nothing on the screen i'don't really know where is the problem from naomi mother board or the game zomebe revenge

please help me

OldFoo · Post by **OldFoo** » Fri Feb 06, 2009 4:22 am

To eliminate the game as the problem, turn on the system without the game cartridge. If the system turns on and gives an error message, then the game is the problem. If the system still does nothing, then it is system related.

OldFoo · Post by **OldFoo** » Fri Feb 06, 2009 2:55 pm

joshua3dg,

Thank you for helping,

Actually i turn on the system without game but it still the same problem nothing on the screen.

do you have other idea to solve this problem?

thanks

OldFoo · Post by **OldFoo** » Sun Feb 08, 2009 4:49 pm

Inbetween the backup battery, the big BIOS chip, and the tiny 8 pin EEPROM chip is a small memory backup capacitor. If that capacitor leaks it will eat the traces under the 8 pin EEPROM chip and render the game brain dead.

EVERY NAOMI I see in my shop gets checked for that capacitor leak problem.

RJ

OldFoo · Post by **OldFoo** » Mon Feb 09, 2009 11:41 pm

channelmaniac

Thank you for informaiotn what i have to do if that happend? can i buy new eeprom for my naomi 1?

OldFoo · Post by **OldFoo** » Tue Feb 10, 2009 2:21 pm

You have to desolder the memory backup capacitor & EEPROM off the board. Clean up the electrolyte mess then put the EEPROM back on the board. Check the traces between the EEPROM and the big Altera FPGA chip next to it for continuity.

Patch any traces that are bad with 30 gauge kynar wire wrap wire.

http://www.sega-naomi.com/forum/viewtop ... 2075#12075 has the info you need for checking the traces.

Use a digital multimeter to check the continuity of the traces.

DO NOT USE AN ANALOG MULTIMETER ON GAME BOARDS - EVER!!!! They put a battery directly in the circuit to measure resistance. This is a BAD thing.

I have replacement capacitors on my website.

RJ

OldFoo · Post by **OldFoo** » Thu Feb 12, 2009 8:43 pm

He said he increased the voltage.

You have to be VERY careful when you do that, as most of the electronics only has about +- 0.5v tolerance before you will blow the device up.