My first Rebuild - I am totally screwed!

[randywhatson]

After watching the "Johns Arcade" video on fixing a dead game, I decided to buy one myself.
So I found a dead Ikari Warriors conversion in an old Centipede cabinet. It was $50, so I bought it.
OK...
The guy said he replaced the power supply but it still didn't work (and said he probably hooked up the switching power supply incorrectly.)
It was so cheap, I didn't look at anything, I just gave him the money and loaded it up.
Got it home, looked inside, and realized I have no idea what I'm doing.
It wouldn't power up. Then I noticed there was TWO interlocking mechs... one by the back panel and another by the coin door.
Now I have power. The light is red on the power supply... and I have 2 "LED's" on the board itself which light up.
However, the monitor is doing absolutely nothing. The neck has NO GLOW. It is an Electrohome G07. I am getting nothing.
I can hear that the speaker is hissing (making some static noise) and I can turn up the noise with the POT on the board. But no game sounds. Just static. The marquee would light up (I'm pretty sure its getting power) but there is no bulb. Simple fix.
The thing I am wondering...
On the switching power supply, there is nothing going to the FG (that is called the Floor Ground, right). Is that necessary?
Also, what is all that crap on the bottom of the cabinet. A bunch of wires... like 6 fuses... some big blue looking capacitor. I have no idea if that crap works, or if it is necessary for it to work. I took out the fuses and the ends are corroded. So corroded, I had a hard time testing them. All of them seem to be in tact. I quickly sanded the ends... tried (but did a piss poor job) to sand the contacts on the equipment in the game, and put them back in.

Then, there are all kinds of connectors that are haning free. I am thinking they are off of the original centipede and not needed. The ikari warriors looks to be a Jamma... with a strance connection at the top of the board (it is dark blue, but not labeled jamma).

Anyway, where should I start?

Again, it seems to have power to the board, but I am not getting any sound. The monitor appears to be dead... but I'm wondering if it is the monitor itself, or a bad connection with the fuses in the bottom of the cabinet (or something else down there).

Any help would be great.

Scott

[offset]

No idea how knowledgeable you are with electricity/wiring, etc.

I start with the basics, use a multi-meter, figure out if power is coming from wall to first connection point inside, check the fuses, etc.

For $50 it could be a huge mess to work through and hacked up, but you never know.

[thegleek]

And the biggest thing you can do here is post PHOTOS of your internals. That'll be the best way this community can help ya out!

[randywhatson]

well, I am a total rookie. But I am assuming it is getting power. The switching power supply lights up, the LED's on the PCB light up, the marque works with the new light bulb, and the speaker is making a static sound.

Should there be a wire going to the floor ground (I think that's what its called)?

How important is all that crap on the bottom of the cabinet?

[offset]

And the biggest thing you can do here is post PHOTOS of your internals. That'll be the best way this community can help ya out!

+1

[thegleek]

I'll use my Centipede as an example. The above photos show, in order, inside upper - inside mid - and inside lower sections. Click on any photo to view the super duper large zoomable image in mega quality.

Everything you see this is a 100% working Centipede. I have no power issues, no glitches, video to monitor is perfect.

[thegleek]

Oh my! ignore the trash you see in the lower cab on the left side. haha when I purchased this gem for $300, I didn't even get around to vacuuming it out yet! doh!

[randywhatson]

I am trying to get pictures uploaded, but can't figure it out.

Anyway, what is that board on the back of the coin box. Mine doesn't have that. But I am assuming it was centipede specific, and since mine is a conversion, I don't need it.

[iankellogg]

the board on the back of the coin box is the original power supply for centipede. if you are planning to leave your game ikari warriors or some other jamma game you don't need the original supply, which you don't have anyways.


I can try to run down some basics but there is a good chance you have a lot wrong.

do you have a multi meter?


You should connect FG to the ground plug that goes to the wall.


If you don't have a multimeter there is basically nothing I can do to help you.

[randywhatson]

http://baltimore.craigslist.org/wan/4994909829.html

I put the pictures here. Couldn't figure out another way.

Anyway, I do have a multimeter.

[iankellogg]

For future reference you can upload pictures to http://imgur.com without signing up for an account.


The board could still be dead.  Just do some sanity checks.  Make sure the power supply has 120 vac going into it.

Make sure there is 5v 12v coming out of the supply. 

Find a way to measure voltage on the pcb. Ideally you want to be around 5v as measured on the pcb.  There should be labeled test points on the board but if you can't find any you can try to measure the voltage on one of the chips.


For the monitor.  Do sanity checks.  Do you get 120vac on the monitor power input.  If so.  Try to find the fuse and see if it has blown.  Start with the simple things and we'll move on from there.

[randywhatson]

thanks man. I'll try that stuff tomorrow. I'll have to look up how to do some of it, but that gives me a great starting point.

[randywhatson]

ok, looks like I have 5 volts dc and 120 volts ac on the switching power supply.

I used a chip on the pcb and got 5 volts.

I don't know how to check the monitor.

[offset]

The monitor should be powered through the Isolation transformer in the bottom of the cabinet.   Never connect a CRT without going through the isolation transformer.

Since yours is using a modern power supply and pcb, that is probably the only part of the bottom that is still being used (and probably the fuses).  An isolation transformer is very important and you need to see if you are getting power at the monitor, but be careful, monitors are no joke, 120v AC (some are 100v) typically and the high voltage when it is working approaches 20,000 volts going into the CRT (which is why you see John discharge monitors all the time before working on them).

Bob Roberts has a good overview/diagram of AC wiring for arcades, basically line voltage from your mains, going through a line filter, then fuses and an isolation transformer to power the switching power supply and monitor.   If the monitor goes through a fuse, pull the fuse and make sure it is ok (make sure game is off)

http://arcadecontrols.com/BBBB/acwiring.html

If you are curious about the crap at the bottom of the wiring, can watch this video.   Old Atari games had their own power supplies and transformer blocks in the bottom
https://www.youtube.com/watch?v=58hvuCvhmis

As you get more familiar with games, you will recognize different power types per manufacturer, etc.   Atari AR boards and the transformer assemblies for example

[randywhatson]

I just really don't know where to check on the monitor to see if it has power. I checked at the interlock switch... which looks like it goes to the monitor?? (maybe, maybe not) and it is reading 120v ac. Where on the monitor do I check. I am afraid to go "prodding around."