Jamma 60 in 1 Arcade

[schuld66]

I purchased a Jamma Arcade Classics 60 in 1 a few years ago and am having problems with it. About 6 months ago, it would not power up properly -- lights by coin slots, but nothing on screen. Then last night, I turned it on and it worked fine for hours. Today, not working again -- nothing on the screen. I have tried holding down the test button while powering on, but still nothing.

I'm no expert on these. Any ideas?

Thanks.

[Nephasth]

Something is impeding the flow of electrons from one copper atom to the next.

[Mike A]

We need some more details to work with. What kind of cab are you using? Maybe some pics. At this point it could be just about anything.

[leapinlew]

You are still in the normal troubleshooting phase. When I have issues with this, I try swapping out components to try and find the faulty component. Swap out the power supply and then try a new 60-n-1 board. Try disconnecting the jamma adapter and just display video.

Some of the guys here would recommend testing at a lower level, but I like to swap parts to determine what part is causing your issue and then, if you choose, see if you can repair the failing part.

In the past, my 60-n-1's have died in a variety of ways from no lights on the board, to all the proper lights lit, but no video signal.

[schuld66]

I opened up the back and took a look inside. I tried a few things, each of which seemed to fix the problem temporarily, only to not turn back on after turning off. I connected a VGA monitor and changed the dip switch (2, I believe), which did display properly on the monitor. I then turned it off, disconnected the monitor, reset the dip switch to its original position, and then it worked fine, until I turned it off again. I turned it off, pulled off the main connector (the long one that attaches to the edge of the board), cleaned the contacts and reconnected. Again, it worked after that, but only temporarily -- turned it off, wouldn't turn back on. Sometimes I could turn it off and back on a few times in a row and it worked. Other times not. I left it running for about an hour, turned it off, and it wouldn't turn back on.

I'll attach some photos:




Inside the front access port:


Inside the back:


Upward towards the CRT:

[schuld66]

So after moving the machine, opening it up, taking pictures and posting them, I tried turning it on and it worked. I can guess that once I turn it off, it won't turn on again until I mess with it again...

[opt2not]

Well if it continues to be a problem, just buy another. These things are stupid cheap. You can get a new one for $30 shipped on eBay.
It’s barely worth trying to fix the one you’ve got.

[schuld66]

So you think it's the board?

[leapinlew]

So you think it's the board?

My suggestion was to swap out components till you find something that makes sense. It could be the power supply as well still. If you have any spares, swap those in and see if it fixes it. The point is, you probably won't be able to troubleshoot it unless you have either some tools to do tests, or different parts to swap in to start ruling out components.

[opt2not]

IMO, any owner of an arcade cabinet needs to at least have a multimeter and the basic knowledge of how to use it. I mean, in the age of youtube tutorials there’s no reason not to learn how to check the voltage coming off the PSU.
I would start there.
A cheap multimeter would suffice. They can be had for <$20.

[Nephasth]

Is there an interlock switch on the back door?

[mourix]

Definitely measure power supply voltages, reseat the jamma connector, and check if the power supply is making proper connection.

[schuld66]

Please pardon my ignorance -- when it comes to electricity, I'm not quite up to speed.

There is a main power supply at the bottom of the cabinet that powers everything. There is also a smaller power supply that I believe powers the board. I have located the power going from the main power supply to the other (when unplugged, the board and game shut down). There are 3 wires -- two purple and a green. I assume the green is ground. These lines lead to the other power supply. I have taken photos of the lines and where they connect to the other power supply. I have a multi-meter -- just need to know what to test and what it should show.

Thanks, and again, I apologize for my ignorance.

[opt2not]

Yes, ok, the 2 Purples are the AC lines coming straight from your wall outlet.  The Green is Ground (or Earth Ground) and it comes from the 3rd prong on the power cord that is  also from your wall outlet.

That Grey little PSU that says Peter Chou on it is the power supply for for your Arcade board, but can also be used for anything in the cabinet that requires 5v/12v, like coin-door lights for example.

The "main power supply" you're talking about is actually the "power center" or "power block", and it consists of Cabinet Switch (or multiple Switches for powering on the cab - like an interlock door switch), a fuse, a distribution terminal, most likely a big Isolation Transformer (it's a big steely looking square coil thing) and an EMI Filter. This Power Center's distribution terminal splits AC from your wall outlet to the small Peter Chou PSU's AC terminals, and also sends power to the Isolation Transformer to power your monitor. It might also split off power to send up to the Marquee Lamp...

Bob Roberts has a diagram of a basic power center or "block" that shows roughly how the power is all connected:


Here's his great tutorial on it, showing how to wire a cabinet from scratch, just to give you some more information on how power works in a cabinet:
http://therealbobroberts.net/acwiring.html

In fact, I recommending perusing more of his topics on his site:
http://therealbobroberts.net/helppage.html

He's got a LOT of information for people both new and experienced with arcade cabinets. Highly recommended reading.

[Mr. Peabody]

IMO, any owner of an arcade cabinet needs to at least have a multimeter and the basic knowledge of how to use it. I mean, in the age of youtube tutorials there’s no reason not to learn how to check the voltage coming off the PSU.
I would start there.
A cheap multimeter would suffice. They can be had for <$20.

Surprised it took that long for someone to say.

[schuld66]

Thanks for the help.

[Nephasth]

Is it fixed yet?

[schuld66]

It's been working without a problem -- not sure why. I did test the voltages -- AC 128.0, DC 9.65. I'm able to power it off and it powers back on fine. I bought a replacement JAMMA board, so if the problem comes back, I'll try swapping that one in.

[Nephasth]

You should have 12V and 5V DC terminals on your power supply. If you got 9.65V, either you took an improper reading or your power supply is shitting the bed.

[schuld66]

I must have had one of the leads on the wrong post (the PS is hard to get at). They all read very close -- a bit under or a bit over.

[keilmillerjr]

Your vdc is incorrect. Surprised your vac is slightly outside +5%. If your using the multimeter correctly, disconnect any load and measure vdc. Also check for a voltage adjustment screw. If you cant get proper voltage without load, its junk. Check connections as well.

[Howard_Casto]

Power supplies are also quite cheap.... for about 50 bucks you can swap out the board and power supply and be done with it. 

[opt2not]

Yeah, those Peter Chou PSU's are quite old now.  I don't even know if his company in Asia is still making these today. There's a good chance the PSU is drifting on the power rails.  I would try to properly measure the power at the JAMMA connector without the board connected. 

The JAMMA pinout is here:


Measure the 5v and 12v pins against Ground.
If those values are looking within spec (the manual says the 5v rail cannot exceed 5.5v), I'd then try measuring the power on the board when it is connected.  The most accurate way is checking voltages on the IC pins:

[lilshawn]

the only thing the +12v is used for on the 60-in-1 board is for the audio amp. the board runs quite happily with just 5v... just without sound.

the audio amp (TDA2003A) will run okay at as low as 8 volts (min 8v max 18v) so, i'm not surprised if it runs at 9V.

I'd still swap out that power supply... they are cheap. you can get something like this...

https://www.ebay.com/itm/External-12V-5V-2A-USB-to-IDE-SATA-Power-Supply-Adapter-HDD-Hard-Drive-CD-ROM-PC/283497613040?hash=item4201c646f0:g:zfgAAOSwxO5c61DZ

and just plug it into the molex on the board. an actual arcade supply is way overkill for what that board needs.

[schuld66]

I've ordered one of the External 12V/5V 2A USB to IDE/SATA Power Supply Adapter HDD/Hard Drive/CD-ROM PC -- found a shipper from US for about the same price. Before I plug it into the molex on the board, I assume I just need to disconnect the current power supply by taking apart the quick connect -- 2 purple/yellows and green/yellow -- that go to the two AC posts and Ground post on the Peter Chou ps.

[lilshawn]

more or less.    be sure to tape off the power connectors that went to the old supply +5 and +12 volts... as the molex is put in line with the jamma connection (so that you could use either connection to power the board), but this also means they will become energised...you don't want them shorting out.

[schuld66]

Put in the power supply and all seems good -- working fine.

Thanks.

[lilshawn]