Recent content by akumajo666

Happy to see you got it working! :)

Virtual Fighter will freeze up if the fan attached to the pcb cage is not adequately cooling the pcb stack. I had the same issue, swapped the fan and I'm good to go. If that doesn't work you may have to test your capacitors on the board As the game is getting up there in age. You should remove...

Usually there are two 5k ohm pots in Sega games. One for the force feedback sensor and one for the actual steering data. Depending on which on you replace you may see one symptom go away or not. You can test the pots with a multimeter in resistance mode. They should smoothly go from 0 to 5k. If...

I don't think mame can simulate malfunctions caused by bad chips. You would have to modify the source and recompile it. If you can board swap at least that would help you narrow down the issue.

Doesn't system 22 use a board stack? You may be able to swap the video board with another system 22 game. The mame source code has some good documentation on the hardware at http://git.redump.net/mame/tree/src/mame/drivers/namcos22.c People often forget the goal of Mame is to document the...

I have a dynamite cop that uses one. Most of my model 2 boards don't have one so only a few games use it I think. Seems like late games on the 2B or 2C hardware revisions are more prone to have them.

Nice, hope you get this up and running. Fun fact, I always thought Virtual Racing was the first game to use fiber optic cables for link mode with another cabinet, but this game uses it too and is from 1989! Sega was always ahead of the times!

Working on a Sega model 1 Virtual Fighter that has missing polygons on the characters. Reseated the ROMs, swapped power supplies, checked voltages so I'm guessing it is the lower video board in the PCB stack. Only other thing I could try is replacing the caps on the board. I get 4 out of the 5...

Is there a ROM test in the test menu? Try hitting the service switch and see what options there are.

You can try reseating the roms on the board and if that does not work replace the capacitors on the board. Caps are heavily used in audio production on PCBs.

The two roms that need to be replaced are encrypted on all original boards. The Hitachi 68000 keeps the decryption key in a battery backed ram chip. Once the battery goes you lose the decryption key, hence can no longer decrypt the two encrypted roms. When you reburn the two roms, you burn the...

You really want to find the datasheets on said chips so you can to know what the equivalent circuit is they provide and hence what each pin of the chip does. Wanted to also provide these great youtube links: http://m.youtube.com/watch?v=7l039y8dX5A http://m.youtube.com/watch?v=omq42Rh4rBQ...

As far as I know reseating chips should be fine. See my post here about the big Hitachi box. http://forums.arcade-museum.com/showthread.php?t=337139 A lot of these mid to late 80s Sega boards used these so it could be dead. I think the Z80 that takes care of the sound on your board might be the...

Just wanted to send another thanks your way SterlingRush. I fixed my other Nanao monitor that had the same issue. It is totally worth it to change out most resistors and the cap in the center of the chasis. Discolored resistors have seen better days. Thanks again and let us know where you post...

This post about toy models had me laughing pretty hard! You never know where the threads are going to go. All in good fun.