new big red, couple questions

Just got a 2 slot 25" big red over the weekend. The cabinet is in sweet shape, went through test mode and all the buttons are in working order. There is something wrong with the monitor though...it only displays on 3/4 of the screen. In test mode I moved the cross-hatches to fill the entire screen, but that causes the upper portion of the display to overlap.

I then opened up the back of the cabinet to access the rear monitor adjustment board, and by unscrewing the plywood the screen went blank, ack! I found a ground wire that looks like it may have been connected to one of the screws. Tried reconnecting the ground wire to a screw, but no dice, the monitor still doesn't display anything.

Guess my first problem is to get the monitor display back. Second issue is getting the monitor to display on the entire screen.

Any ideas?

Thanks!

What color was the wire that came off..?

Green..?

You may need to run that wire to a better ground..

Just be carefully when messing around in the back of the monitor..
(Deadly Electrical Shock)

chris1 said:

What color was the wire that came off..?

Green..?

You may need to run that wire to a better ground..

Just be carefully when messing around in the back of the monitor..
(Deadly Electrical Shock)

Click to expand...

Yeah, it's green. Looks like it may have been attached to one of the screws that goes through the back plywood piece. What would be a better ground? Monitor chassis?

Thanks!

that's the frame ground wire, leave it as it is... on a screw on the monitor frame :-)

DaemoN said:

that's the frame ground wire, leave it as it is... on a screw on the monitor frame :-)

Click to expand...

Ok, so it's cool to ground it to the metal frame? Just want to be safe As far as re-grounding, will a bolt and nut do or is there more to it? I didn't see a screw in place when it opened.

Bounty Hunters read on!

K, Christmas crazyness is over, so I was able to play with the cabinet a bit more. Here's the kicker...got a New Year's party coming up and would really like to have the Neo Geo playable by then.

If you provide the tip that gets it working by then I'll send $10 to the PayPal account of your choice. Must reply to this thread, first post that covers it gets the cash. If the power supply is dead guess it's a moot point, no time to order a replacement by then

Check out the top of the thread for more background. Basically the dedicated 2 slot worked initially, but when I opened the back a ground wire fell off and nothing seems to work.

I regrounded the loose ground wire to the monitor frame. Turned the game back on and no change. I put a voltmeter on the ground and +5v pins on the board and it's NOT getting power, at least not much, coming in at 300ish mV. What's odd is that the marquee light does come on, but nothing else does, no cp LEDs, no monitor pic, no board LED, etc. The power supply sounds ok, still gives the whirring sound (at least it sounds ok to me )

I also checked the main fuse by the coin door and it looks good, no blackening inside. Is a visual scan of the fuse enough or is there another way I should test that?

Oh yeah, the cabinet was plugged in when the ground wire became unattached.

What's next? Are there other fuses to check? How can I test the power supply directly? Why does the marquee light come on but nothing else?

Try this: using the multimeter, do a continuity test on all the fuses you can find. If one doesnt work, replace.

Fuses sometimes get bad and they dont ''blacken" inside!

I hope this helps ya, I know how it feels to have that urge to get the thing playable :P

Since you can test the 5V, test the 12V line as well. If it works but the 5V doesn't then it's probably a bad power supply. You can either fix it, or replace it. It's usually easier to replace it though, it's not really expensive.

If you don't want to wait until a new one can arrive you can use a spare computer power supply as a temporary fix until it does. Just connect the right voltages, and ground the light green wire on the ATX connector(that's the power on wire for the PSU).

The monitor could probably use a cap kit though once you get the system going. The monitor is probably on, but the game board apparently isn't getting power. Look at the neck of the CRT and see if it is lit up when you have the cabinet powered on.

DaemoN said:

Try this: using the multimeter, do a continuity test on all the fuses you can find. If one doesnt work, replace.

Fuses sometimes get bad and they dont ''blacken" inside!

I hope this helps ya, I know how it feels to have that urge to get the thing playable :P

Click to expand...

Thanks for the tips! How does one do a continuity test? What sort of output should I be looking for from the multimeter? Yeah, beautiful cab, but it's eating me up that I can't play it

Reznor007 said:

Since you can test the 5V, test the 12V line as well. If it works but the 5V doesn't then it's probably a bad power supply. You can either fix it, or replace it. It's usually easier to replace it though, it's not really expensive.

Click to expand...

Will do, I'll test it tonite after work.

If you don't want to wait until a new one can arrive you can use a spare computer power supply as a temporary fix until it does. Just connect the right voltages, and ground the light green wire on the ATX connector(that's the power on wire for the PSU).

Click to expand...

I may end up going this route. What's a good place place to ground the ATX connector?

The monitor could probably use a cap kit though once you get the system going. The monitor is probably on, but the game board apparently isn't getting power. Look at the neck of the CRT and see if it is lit up when you have the cabinet powered on.

Click to expand...

Will do, test tonite A cap kit is my next step, once I get the cabinet fully functional.

Hopefully something here will do it.
Thanks!

Here's what you do (usually):

On the multimeter, choose the lowest ohm setting. It should have something that resembles a little speaker or 'sound wave' drawing on it.

Now using the 2 legs of the multimeter, touch red and black, it should beep or make a whirring sound.

If it does, then your multimeter has a continuity test.

Now to the cab:

you touch one side of the fuse with red and the other side with black (doesnt matter what color goes where).

It'll test it for continuity. If it beeps, its good, if it doesnt, replace it :-)

I hope this helps.

- Daemon

bones said:

I may end up going this route. What's a good place place to ground the ATX connector?

Will do, test tonite A cap kit is my next step, once I get the cabinet fully functional.

Hopefully something here will do it.
Thanks!

Click to expand...

Whenever I have to use a PC power supply I just take the light green wire and connect it to the black ground wire that is right next to it.

If you look at the ATX connector with the wires going up, and the snap lock part facing you, the green wire is 4th from the left.

DaemoN said:

Here's what you do (usually):

On the multimeter, choose the lowest ohm setting. It should have something that resembles a little speaker or 'sound wave' drawing on it.

Now using the 2 legs of the multimeter, touch red and black, it should beep or make a whirring sound.

If it does, then your multimeter has a continuity test.

Now to the cab:

you touch one side of the fuse with red and the other side with black (doesnt matter what color goes where).

It'll test it for continuity. If it beeps, its good, if it doesnt, replace it :-)

I hope this helps.

- Daemon

Click to expand...

My multimeter has a kiloohm symbol, so I set it to that...had to look up the symbol on the net (been a few years since college!)

When I touch red to black using that setting no noise. Just in case, I tried it on my fuse and no noise there either. Is it safe to say this meter doesn't have a continuity test?

I'll probably head over to Radio Shack and ask about getting one. What should I expect to pay? Can you purchase a continuity tester separate from a multimeter or is that how they always come?

I may just buy a replacement fuse on the chance that solves it. Besides the main fuse that's up front by the power swich are there other fuses in the cabinet? Where can I find those?

Thanks!

Try setting your meter to diode mode(the arrow with a line). That's usually where the continuity test is.

The common places for fuses in games are right inside on the power line/before power supply and isolation transformer. one inside the power supply, and one on the monitor deflection board.

When you removed the plywood.... did it fall into the cab hitting the neck? I hope not.

Tiptonium said:

When you removed the plywood.... did it fall into the cab hitting the neck? I hope not.

Click to expand...

It may have, I didn't see what it brushed against at the time. When I found the loose ground it was dangling inside the cab not touching anything. I regrounded it to the monitor chassis after that, but nothing came on except the marquee light.

Is the neck part of the monitor? If it did hit it what could that have done?

Thanks!

If it hit the neck then there is a good chance that the neck was cracked as they are quite fragile. Does the monitor have a protective frame around the neck or is it exposed ... just sticking out. I only ask since I had a cab door pop off and hit the neck on a monitor that I had... I heard a faint hiss and that was that. I ended up buying a new monitor.

Can't recall if the neck is protected or not. I'll have to check tonite...damn work always seems to get in the way of play

Tiptonium said:

If it hit the neck then there is a good chance that the neck was cracked as they are quite fragile. Does the monitor have a protective frame around the neck or is it exposed ... just sticking out. I only ask since I had a cab door pop off and hit the neck on a monitor that I had... I heard a faint hiss and that was that. I ended up buying a new monitor.

Click to expand...

Do you still have that monitor?

I'm wanting to build a monitor, and I need a matching deflection board+neck board+yoke.

My old meter has a CONT ...setting for continuity...maybe your has that..

I'd just set it to each setting and touch the leads together real fast until I heard a beeping sound..if I didn't have such a setting..


My old meter really doesn't look so crappy as in this picture,it's just when I shrink the pictures it really looks like garbage..
The damn old think works well though..

Here's the Power Supply that I bought...(If you need it)

(I told another member about it but he can't use it..)

The guy has another one...
I was going to bid to win on this one for a spare,but someone here may need it..


Power Supply 150W Switching Neo Geo MAME NR

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=3263677013&category=13718

I have two of the Computer Power supplies around,I have no clue what Computer they are from..I bought them at an Arcade Auction just to mess around with..

Round 2 of testing, here's my progress so far or lack of

Before diving in I've gotta say once again...Radio Shack blows. I went there in search of a continuity tester and the old guy there didn't even know what one was! I found the testers built into a few multimeters, but the cheapest one with this feature was $70! So I just bought 4 replacement fuses for $2 instead

Anyhoo, here's what I've done:
Installed a new main fuse, no change.
Tested the 5v & 12v lines on the JAMMA pins,neither get power
The monitor neck is glowing, so that seems to be ok.

The monitor does still sound like it is powering up and has a faint flash or 2 of light every few seconds so I'm thinking it's fine and more of a matter of power.

I'll look around for other fuses to replace later tonite. In the mean time, how does one test the power supply lines directly? It's not getting juice to the JAMMA connectors so I'm wondering if it's a wiring issue from the power supply to the JAMMA edge. Guess I'd like to confirm the power supply is dead before swapping it out.

Chris1, thanks for the link, I may end up bidding on that if my power supply turns out to be dead.

The marquee light still lights up even though nothing else seems to be getting power...is that a clue of some sort?

Thank you all for the replies, I'm definitely learning a thing or two

Naw, that monitor is long gone. I could not find anyone willing to repair it. It was quite old (1990-ish) with a lot of burn in. It ended up at the dump delivered by me personally.

Reznor007 said:

Do you still have that monitor?

I'm wanting to build a monitor, and I need a matching deflection board+neck board+yoke.

Click to expand...

Tiptonium said:

Naw, that monitor is long gone. I could not find anyone willing to repair it. It was quite old (1990-ish) with a lot of burn in. It ended up at the dump delivered by me personally.

Click to expand...

Damn. Just a tip though, always keep the circuit boards and yoke from monitors. They are always fixable, and you can use an old TV CRT(since they rarely have burn in). I have done this before, and it had excellent results.

Hey, did you check the amperage on the fuses before buying replacements? Because you can't just use "fuses".

There are different amperages, too low and the fuse will blow easily. Too high, it will hold on even when theres a bad power charge, so it would burn your equipment instead of the fuse...