Jail Break - Nintendo - CPU board issue - assistance appreciated.

[eg0e]

Hi all,

I have a table top version of Jail Break, Nintendo, I think it's 1984, but I'm not at home right now.

It was working at one time, but I haven't plugged it in in about a year, I just moved and started a game room in my new house, I plugged it in and.... no game

The monitor appears to be working properly, it powers up and I get a nice white screen, but I get no game graphics and no sound, so it appears that the CPU is not functioning.

I checked both the 5V and the 12V power into the CPU board and both are reading good, I don't see any scorched components or burned traces on the board, so at this point I'm not sure where to go with the troubleshooting. It came with a sheet for the dip switches and a sheet for the ribbon cable pinout, but no other manual.

Any ideas on what I can check next would be great. I have an AAS in electronics and am well versed in using a multimeter and troubleshooting to a component level, but I've never repaired one of these machines before, and without a circuit diagram, I don't know what I should be looking for to determine the faulty component.

Thanks in advance!

Seth (eg0e)

[fredster]

Obviously you opened it up and could tell where the power was.

If you haven't used it in a while, did it get tossed around?   First thing to do is unplug it, go in and make sure you have all the connections where they are supposed to be.  Next, turn it back on and see if it plays blind.  Do you hear the game sounds when you coin it up? 

As for the monitor, it's odd that it's all white. If anything, you should see garbage.  If you know how to turn down the screen, do it. Make sure that nobody has twisted the dial all the way up.

Tell us what you find.

[eg0e]

Thanks for the speedy reply, I love active communities 

It was moved, however it wasn't tossed around terribly much. I went through and checked all the wiring harness connections and made sure all the wires going into the harnesses were secure, per your suggestion.

It does not play blind. I made sure that all the dip switch settings were correct for sound and that the speaker was hooked up. I even flipped the dip switch for demo mode which I remember made tons of obnoxious sounds, "The warden has been kidnapped, rescue him" and music; however the unit now just stands silent.

I checked the connection for the ribbon cable harness and everything looked nice and clean; I didn't see any corrosion or oxidation on the traces where the ribbon connector slid onto the CPU board. I rubbed them a bit with a pencil eraser to clean them anyways... no effect.

I'm not sure which knob you are referring to as the "Monitor" knob. There are tons of knobs on the monitor and monitor assemblies: Sync, R, G, B, Brightness, etc. I did adjust the brightness knob a bit but still had a blank white screen.

I took some pictures, the ones with the monitor on you can see the scan lines due to the refresh rate of the monitor versus my camera, but live it's just a blank white screen.
The CPU board looks like it's in great shape, I made sure all of the EPROMs were well seated and everything looked in place, which they all were.

Anyways, hopefully this sparks some more ideas to have me try.

Pics below.

[fredster]

On the back of the monitor there is a "flyback" transformer.  On one end you see a suction cup, and on the other is a black assembly.  On that assembly are two knobs. The one close to the top of the part is the "focus" screen, and the one under it is the "screen".  The "screen" is the brightness.  If you turn it up or down, then the monitor will get dim.  It's kinda hard to reach in one of those cocktails like that, and it looks like it doesn't matter, as the monitor is working.

But if the game is dead when you are sure you have the +5 and +12 volts on the game, it sounds to me like your board is dead.  If you are savvy, there are some basic trouble shooting things you can do to fix that.

Why? I am not sure. Most of the time something happens to the power supplies, and when that happens, the boards get a surge or don't have enough power to function.  Usually you can tell because you will see at least garbage when you turn the game on and off.  But you have power. 

Try this, just for the sake of it.  Find your +5 VDC, then flip your meter to AC.  You should see no more than .5VAC on that. Try it on the +12V DC portion too.  If you see more that .5VAC, then one of the caps failed in that power supply and you have too much AC "ripple".  That may tell you why it failed.  Whatever is in there can be replaced with a new switching power supply for about $30.

Keep in mind that game is very old.  It's from 1985.  I had a game called "Atomic Punk 2" that died and when I decided to check, the capacitors had rotted off the board! They leaked all over the chips and shorted one out.  Perhaps one of the 7805's on the board decided to give out and the board isn't powered, or whatever. 

If you don't have a manual, and you want more info on the game check this link. 

http://www.arcade-museum.com/game_detail.php?game_id=8221

If you find the PS is okay, and you really like the game, my advice is to just buy another board for it on ebay. I noticed in the klov listing link that there are parts for it.

If you want to jump in and try and fix it, here's where to start

http://forums.arcade-museum.com/showthread.php?t=177192

[eg0e]

Thanks,

I've ordered a new PCB from ebay, hopefully all works well!

[fredster]

Great, and in the meantime, don't run that monitor very long without some load on it.  It's not good for it. "Load" being a signal from a game.

But before you get too far, make sure that Power supply is actually working.  You always have to have the proper power.  Most failures occur because the P/S is bad!

The monitor will have a detachable plug on it.  Pull it and then try that board and check the power right at the connector. Look at where the PCB connector traces are at and put your probe on the board right there and see what it reads.

A difference of +/- .25V on the 5Vdc can cause it to screw up .