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View Full Version : MISSILE COMMAND and NEO-GEO 6slot for GAME ON



GameDude
15th January 2009, 12:37 AM
Barry from GAME ON in Brisbane asked me to look at his Missile Command PCB and the AR2 PSU as well as a NEO 6slotter he was having problems with.
Many may have noticed the Missile Command Cabinet not working at Game On recently....
Missile Command - Yellow Screen.
Noted some corrosion around the POKEY chip and a mildly dirty edge connector, cleaned up the edge connector and powered up to find the game running OK, Set dip switches for freeplay and had a few goes, flexed PCB ect no problems ran for about 8 hours no crashes, tried test mode and passed system self tests.
I did not have a harness to power the AR2 PCB but as I was told the all voltages were present and correct on the PCB when powered I only checked the caps with an ESR meter and found no fault, the PCB had already had the sense mod done as well so not much more I can do untill this Sunday when I return them for re-installation.
To finish the work I cleaned all the corrosion and rust then laquered the PCB in PCB laquer to seal against further environmental attacks, purely a preventative measure and not really anything to do with fixing the PCB.

NEO GEO 6 Slot.
Problem was constant resetting.
I found that the board would constantly fail randomly on any game usually with a memory error, the error changed every time sometimes video sometimes system ram. I checked power and found the voltage before and after the harness dropped by .3volts (not to good) I also checked the slots and found that even minor vibration and movement upset the games.
To fix I used an eraser and cleaned the JAMMA connector until shiny new and used a PCB cleaning solvent and a fine grade sand paper folded and inserted into each slot for a gentle rub down.
The PCB now shows a more healthy .02volt drop on the harness and no more than .1volts drop across the entire PCB when fully populated.
I can now wiggle all cartridges without having any reset or corrupt.
A side note as this is a very common issue with cartridge based systems is the proper cleaning of the slot and cartridges will keep them in perfect working order... Old wives tales about blowing cartridges and hitting them on the ground are crap!
Use the eraser as well to clean cartridge edge connectors as well and brush away any debris before inserting again.....
To finish up I also added an external battery holder as the original battery had been removed.

Mr_Staypuft
15th January 2009, 12:52 PM
Fatal Fury? Puzzle de Pon?

I hope they're just "Gamedude's test carts" & not the Neo games you're currently exhibiting Barry! :o
(You still have the cool games don't you? Metal Slug X? Magical Drop 3?)

GameDude
15th January 2009, 01:08 PM
Ummm... yeah they are my test carts... not barry's!! :lol

Mr_Staypuft
15th January 2009, 02:45 PM
Ummm... yeah they are my test carts... not barry's!! :lol

Thank goodness!

BTW - it was interesting to see Barry's *UK* Neo 6 slot cabinet at Game On.
(So different to the Aussie/"Pacific" style cabs we have.)

NateDizzle
20th August 2010, 10:39 PM
I often read repair logs late through the night, This one is one of my favorites. Good work Dorian

Davefjedi
20th August 2010, 10:59 PM
Me to Mr click n refresh I read this last year but should say good work :)