Tron Cabinet - powers up, but no picture/sound

tronwong

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I recently came into possession of a Tron cabinet and when plugged in the lights come up and the monitor comes on, but it just displays a black screen and I believe that there is no audio coming through.

We got the back open, and we've been looking around for issues. On the power supply, there is only one fuse despite there being two slots. I recently placed another fuse into the empty slot and now the audio is a series of audio sputters.

This makes me believe that there is no audio and video coming through, but nothing from the actual game is going in. Is there anything else I should check for this particular game? I don't particularly have experience dealing with this type of thing either, would it be preferred to go to a professional and how much does one usually cost for this type of deal?
 
from what i would think you most likely have a dead power supply. this is what it looks like. image courtesy bob roberts.

90412-1.jpg


the first thing i would check is to make sure all the wiring harnesses to the power supply and game pc boards (the 3 board stack on the left side of the cabinet) are plugged in. also, check your fuses on the transformer block (the big brick in the bottom of the cab.) be gentle with the short ribbon cables that connect the 3 pcb's together, as they are pretty delicate and may break if moved or bent.

after that, assuming everything is good, check your voltages on the power supply. if there is nothing there you will get no game.

here is a link to the manual that tells you how to check the voltage. you'll need a multimeter, preferably digital one to check them.
http://arcarc.xmission.com/PDF_Arca..._Midways_MCR_II_&_III_Systems_(July_1983).pdf

page 17 tells you how to check the various voltages (+5, +12) and page 18 will show you the points on the power supply where you put the multimeter leads to check them. report back what you find.
 
what do you mean interconnects? Do you mean the ribbon cables? I had heard there were problems involving the ones that were there.

I had read something about a purple wire that was a problem for everyone and I cut it and it didn't do anything. This doesn't affect anything does it?

So you really think it is the power supply dying that would cause the game to just not boot up like that? I didn't think it was a power supply problem considering the monitor, speakers, and lights all get power. I was worried it would be something about the board being broken.

I'll look into fixing the power supply. I already got through all the fuses though.
 
the power supply wouldn't affect the monitor or lights, that's ac power.

The power supply board pictured before, would affect game play.
 
When you went through the fuses, did you use a multimeter to test them or just eyeball them? You don't want to rely on just looking at a fuse to see if it's good or not. The multimeter would also be very important for checking the power supply voltages to make sure are correct. If you wanted to get more into repair, even just the beginning stuff, a multimeter is really a must own and the good news they are inexpensive. One other suggestion would be seeing if there is another forum member local to you that might be able to help. It would be a great way to learn a few things and be cheaper than hiring someone like a game operator to fix it for you.
 
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ahhh, I'll go ahead and try and get a multimeter as well as switch all of the fuses.

Does anyone know any members that are local to New Orleans, LA?
 
ahhh, I'll go ahead and try and get a multimeter as well as switch all of the fuses.

Does anyone know any members that are local to New Orleans, LA?

I don't know of any KLOV members in New Orleans offhand, but you're very close to Bob Roberts whom cleverlyj mentioned above. He's a big source for arcade related parts and a great guy to deal with. If you end up buying parts from him they should be there super fast. :)
 
ahhh, I'll go ahead and try and get a multimeter as well as switch all of the fuses.

Does anyone know any members that are local to New Orleans, LA?

i would definitely get a meter and check the power supply board before you go too far. you may have a working +12 volts providing the audio amp power (and associated crackling noise) but no +5 causing the game boards to not run.

you can get a cheap digital multimeter from radio shack, if you have one nearby. i would recommend replacing the ribbon cables on the pcb's regardless of condition, just to rule that out and to also not cause any issues in the future...

http://therealbobroberts.net/mcr.html

as far as most parts, you're best going through bob. shipping is real fast, and his prices are good.
 
Hey,
It's been a while since I've been able to get back to this again but I finally checked some of the voltages. All of the power supply levels appear to be pretty good. The +12 is at 11.8 or so and all of the other ones are in the recommended range. The +5 however is at 0.7 volts. How do I fix this?

Also, the the board that sits at the very bottom of the cabinet with the big battery looking blocks appears to have no electricity running to it no matter where I try to look. I replaced all the fuses and there is no power running between any of them though. Does this have anything to do with the power supply?

I recently saw this thread and I could just buy another power supply. Would that be the recommended thing to do if my skills at fixing these types of things are limited?
http://forums.arcade-museum.com/showthread.php?t=139851&highlight=tron+power
 
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That would be your transformer assembly. You want to be very sure that is wired up correctly. Look for hacked wires or such, but be very careful, there's ALOT of voltage there. If it's not wired correctly, you will not recieve any power to the lamps, marquee, monitor, nothing. If your transformer has problems I'd definitely be unplugging the PCB stack until that's resolved.
If it's a dead short that's taking your 5v down, check your screws that fasten the pcb's to the plastic standoffs. Run a heat check on them and you may find one that's quite hot to the touch. Once that's resolved you should have your 5v back. Good Luck Program!!

http://www.zinfer.com/tron.htm

Hey,
It's been a while since I've been able to get back to this again but I finally checked some of the voltages. All of the power supply levels appear to be pretty good. The +12 is at 11.8 or so and all of the other ones are in the recommended range. The +5 however is at 0.7 volts. How do I fix this?

Also, the the board that sits at the very bottom of the cabinet with the big battery looking blocks appears to have no electricity running to it no matter where I try to look. I replaced all the fuses and there is no power running between any of them though. Does this have anything to do with the power supply?

I recently saw this thread and I could just buy another power supply. Would that be the recommended thing to do if my skills at fixing these types of things are limited?
http://forums.arcade-museum.com/showthread.php?t=139851&highlight=tron+power
 
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That would be your transformer assembly. You want to be very sure that is wired up correctly. Look for hacked wires or such, but be very careful, there's ALOT of voltage there. If it's not wired correctly, you will not recieve any power to the lamps, marquee, monitor, nothing. If your transformer has problems I'd definitely be unplugging the PCB stack until that's resolved.
If it's a dead short that's taking your 5v down, check your screws that fasten the pcb's to the plastic standoffs. Run a heat check on them and you may find one that's quite hot to the touch. Once that's resolved you should have your 5v back. Good Luck Program!!

http://www.zinfer.com/tron.htm

I have power to the lamps, marquee, monitor and speakers. Literally the only thing that doesn't come on is just the game itself. Does that still mean the transformer at the bottom is running correctly?

Can you explain a little more what you mean in the second paragraph? I imagine the problem I am running into is that there the +5V is too low so it isn't powering the game boards. Do you mean that I need to check just the screws on the game boards? I'm sorry, just having trouble understanding the last part.

Should I go ahead and try to do that newer power supply as well as switching out the ribbon cables and that would just be an overall fix for nearly everything?
 
I imagine the problem I am running into is that there the +5V is too low so it isn't powering the game boards.

That is your problem. Your options are the switching power supply mentioned above or rebuild the original power board with a kit from Bob Roberts. The switching power supply will be easier but will cost more money. Some folks have noted that a switcher in a Tron produces hum, some say they get no hum. If you can solder, get Bob Roberts' kit.
 
I have power to the lamps, marquee, monitor and speakers. Literally the only thing that doesn't come on is just the game itself. Does that still mean the transformer at the bottom is running correctly?
Ok, well it sounds then like your transformer is doing fine and is passing plenty of electricity to your Power supply PCB.

Can you explain a little more what you mean in the second paragraph? I imagine the problem I am running into is that there the +5V is too low so it isn't powering the game boards. Do you mean that I need to check just the screws on the game boards? I'm sorry, just having trouble understanding the last part.

Depending on your standoffs, you may have screws that are connecting your boardstack together. If so, the screw can ground and cause a short which will do strange things to your 5v, like pull it down to .07v. The standoffs are located at each corner of the pcb stack to the right as your looking into the back of the cabinet. Do you have screws going into the standoffs or are they all plastic inserts? If I recall one side is plastic insert, the other screws in from the board with metal screws. The screw can cause a short.
Your boardset needs 5v to operate, that's 5v at the board, not the power supply pcb. You'll lose half a volt just from the harness travel of electricity.

Should I go ahead and try to do that newer power supply as well as switching out the ribbon cables and that would just be an overall fix for nearly everything?

Well, I'm not so big on throwing in a switcher without knowing what's wrong. Seems your being pushed in that general direction. Ribbon cables are an excellent start. You can use the old style SCSI cables for that but you have to have them plugged in correctly. But you do need to be sure of your voltage measurements at the boardset.
If all else fails, I don't know if he's still around, but an excellent Tron repairman was Richard Cross out of Canada. Haven't heard from him in a long while. [email protected] used to be his email. There's also another good Tron tech here on Klov but I'll have to look that one up.
 
Hrm, had a misfire on the quoting mechanism on that last post. Anyhow, CDJUMP is a great Tron tech. Do a heat check on your boardstack, check the standoff screws for shorts, do a double check on your outbound 5v from the power board, not the transformer. Unplug the pcb stack entirely. Do you have a good 5v at the power board then?
I'd also recommend removing that ancient battery on there, if it's still there and replace it with something that you can isolate from the power board. But that can always be done later.
You'll probably end up adjusting your outbound voltage for something like 5.25v. Check your adjustment on the pot that allows you to adjust your 5v.
But most of all, respect electricity, it will remind you if you don't.
 
Having taken a better luck at the power supply board there is corrosion ALL OVER IT. Is this really what the big problem probably is that could be fixed by just replacing it?
 
Having taken a better luck at the power supply board there is corrosion ALL OVER IT. Is this really what the big problem probably is that could be fixed by just replacing it?

Yes. The power board is a common failure point in MCR games. The battery eventually corrodes and leaks acid all over the board. Whenever I get a new MCR game, the first thing I do is remove the battery. If the board isn't too nasty, Bob Roberts' shotgun kit will usually fix it.
 
Depends on how bad the corrosion is really. The definition of corrosion over 30 years can mean different things to different people. :) But if it's heavily corroded by the battery, that could be a problem. A picture says a thousand words.
Usually the first thing I do when I get a cabinet is remove the pcb onboard battery and hit the damage with some vinegar solution and a toothbrush followed by isopropyl alchol and toothbrush.
But if it's that bad - you could either scout out another power board or go with arcadeshops MCR power replacement board.
 
have you tested the 5v output from the power board with the pcb/harness removed?

Having taken a better luck at the power supply board there is corrosion ALL OVER IT. Is this really what the big problem probably is that could be fixed by just replacing it?
 
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