Monitor Isolation Power Identification

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Hi!

I'm starting a new repair project and have an identification question. Is this a monitor isolation power supply in the picture?

It is a birdie king 2 with a Shinlee EM-201 monitor chassis. The monitor does not turn on and there is no neck glow. When the arcade is powered on I can hear a punch sound in the speakers initially but no game noise... but nothing on the screen. Do I have an isolation transformer issue? Any ideas? Thanks!
 

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that looks to be your iso.

measure the windings on either side and see if its the same input in and out. ac is what your looking to measure.

Peace
Buffett
 
Isolation transformers almost never fail.

Check the voltage going in to the monitor chassis - should be 120v or somewhere around that.

Chances are you just have something wrong with the monitor itself = dead monitor/no neck glow is a common failure mode. What kind of monitor is it? Can you take a picture of the monitor chassis?

-Ian
 
I am pretty sure it is a Shinlee EM-201 monitor chassis I have attached pictures of the chassis and the Philips monitor.

I will be checking the voltage when I get home today. I was able to swap out power supplies with a known good one and the speakers would pop when the machine was plugged in but no neck glow and I could not hear the game playing at all. That's why I was questioning the Isolation transformer since the monitor wasn't powering up.

What do you mean by common failure mode? Do they have different modes that can shut it down?

Thanks for the help!
 

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I will be checking the voltage when I get home today. I was able to swap out power supplies with a known good one and the speakers would pop when the machine was plugged in but no neck glow and I could not hear the game playing at all. That's why I was questioning the Isolation transformer since the monitor wasn't powering up.

Sounds like the game isn't powering up either. It should boot and play even if there is no monitor in the cabinet. You should be able to coin up the game and hear it running. Unless, of course, it's set in test mode. Check the voltages at the game board, make sure the power supply is adjusted correctly.

What do you mean by common failure mode? Do they have different modes that can shut it down?

Lots of different ways monitors break. But a completely dead monitor is fairly common. For instance, the HOT fails and takes out the B+ fuse, which pretty much renders the whole monitor dead. Filament voltage is usually derived from the flyback, so if the horizontal circuit isn't working, you won't get any neck glow or HV. But, it could be lots of things - like a disconnected wire, a blown fuse in the cabinet wiring, etc. Start by checking for AC voltage at the monitor's power input. If it's getting power, and it's not coming on, then you have to do some investigating in the monitor itself.

But it sounds like you have two problems. Divide and conquer. Start with basic voltage checks first, and work your way through the game. Do you have any other games? You can plug the video cable into a known working monitor, and see if you're getting any output from your game board.

-Ian
 
Thanks Ian!

I do have a few other games so I can try and test it out.

Can you tell me where you test the voltage at the game board?

I should mention that I realized last night when I was trying to power it on with the back off that is has a safety switch on it. upon pressing the switch I hear the punch of the speakers but I have not fully tested out adding credits and listening for the game. The sounds has always been really faint on the game last time it was working. Ill definitely do that first to try and eliminate some possibilities.

I did check the voltage coming out of the power supply (DC) and got nothing so I am pretty sure that is dead. The power supply is getting AC power just not pushing out the 5V or anything. I ordered a new one last night but can pull one out of a working game as well to test again.

I will do some dividing and conquering and report back.Thanks for the help!
 
***Update***

Im continuing to work on this game and the game does play blind. I can coin up and play the game but no video.

Monitor doesnt appear to be getting power... No neck glow.

The wire coming out of the isolation transformer has a molex connected instead of what Im used to seeing which is a 2 prong connector. I tested voltage inside of the molex connector but cannot get a good reading. Since the wires go down inside of the iso trans... whats the best way to test voltage? at the monitor harness? Any ideas?

Thanks!
 
Test it right at the transformer. The input lines go into the bottom of it and the output is at the top. I see in this pic that wire is coming out of it and coming up is where to test it there.

And at the monitor, there should be a removable plug that the wire from the transformer goes to. It should have at least the two AC lines. It might have more. You can unplug it from the monitor and check there also.

If nothing else, you can just cut that wire and test it directly. But I bet you can unplug the monitor too.
 
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Here are some pictures of why Im confused... after taking the iso trans off here is what the bottom looks like.

It goes in and out of the bottom... and the wires run deep inside where I cannot test. (inside of the paper thin metal inside of the iso trans) How do you test this?

There is a removal plug but its a molex connector. When I unplug it and stick the leads inside I get a very weak reading at .004 volts. Not sure if its a bad reading or not is why I was wondering if I could test at the chassis? (Second pic)
 

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That transformer looks pretty nasty, like it has be water damaged or something. Usually they are yellowish, but that one is rusty.

It's really pretty simple. The wire that comes in from the plug is the "INPUT" to the transformer. The wire going up to the monitor is the "OUTPUT". That wire coming out has to end up somewhere on the chassis.

That lead that you show in the second pic probably goes to that big black wire that goes around your TV tube. That's for the degaussing coil around the tube. (At least that what it looks like).

Unplug the wire from the transformer at the monitor chassis. Test it there. It's just like unplugging a TV. If it's soldered directly to the tube, then get down by the transformer and cut it. and test it. If you get something like 100 to 120V, it's probably good. Then splice it back together. after you are done.

Some of these transformers are actually step down transformers. They will show about 100 to full 120V AC. If you are getting nothing, or something less than 100V, that part is bad. Transformers are cheap and plentiful.

Under no circumstances try and plug the Monitor into the wall. The transformer is used to decouple the house AC power. Plugging in the monitor without an isolation transformer will immediately destroy it.

EDIT:
I looked at the second set of pics, and I see your problem. You can't find it as it's in that mass of wires. You will have to cut that line to the monitor to test it properly. In your first post, cut the wire that's banded together and then plug the thing in with the probes there. Then post back.
 
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Gotcha.. yeah I understand all that. I did follow the "Output" to the chassis and that is what I was pointing to in the picture not the degaussing coil (even though that may be in picture as well) It is soldered directly to the chassis.

I think i understand what I need to do.. splice and test. If bad then try using a different ISO transformer.

Thanks for your help!!

Attached I've circled where the AC lines attach to the chassis. Can I test here?
 

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I tested the AC line going into the iso and got 120 V.... I then tested the line coming out of the iso after cutting the wire and got .006 V

Many of people have said that isolation transformers almost never fail.. Im guessing mine has. Can anyone recommend a good place to pick up a new one? It says 120V on my chassis but I know some of my other games have 110V iso's

can you buy switchable ones?
 
That's the easy part. Here is the source, expect at least $7 for shipping. If I were you I'd look for other parts you may need before you order, as this man has a lot of parts.

http://therealbobroberts.net/parts.html#tbs
Isolation Xformer 1:1 $12.00

Bob just takes checks, and if this is the first time you have bought anything from him he will wait for the payment to come and clear. After that, he will cross ship to you and the parts will get to you priority mail.

Visit his main page and you can see a whole bunch of information on transformers and wiring.

Looks like the one you have is water damaged to me. It's also the shielded type. I don't think it will matter. The shielded type is a nice feature to prevent interference, but it's not required. What does matter is if it actually is a 1:1 transformer.

I don't think they make a switching one, and you really don't need that. All you have to do is verify that the monitor takes 100V or 120V and that will be in the schematic. I think the monitor gurus here can help you with that. I have never seen this type of monitor, and I have no idea what it really takes.

Once you verify that this Shinlee EM-201 takes a 1:1 transformer, you can order the right one from Bob Roberts.
 
Cool man thanks for the help!!!!

Attached is the specification.. looks like 120V... I'll post back with the results.
 

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Got the isolation tranformer and installed it.. I could hear the monitor power up and got voltage.

The only issue is now I hear an extremely loud whining from the flyback and saw a little bit of smoke. I immediately turned off the game. I did get an image on the screen... it was a small square in the senter with a jumbled pictured with verticle lines.

Can anyone help me with next steps? Do I need to replace the flyback? Any help is appreciated! Thanks!
 
It's not unusual at all to have the funny things on the screen when you turn the game on. It takes some games a few seconds to "boot" and they have all kinda weird characters on until the game is on.

How long was it on? Obviously enough time to get a picture, (that's a plus). It means that most of the thing is working. Smoke out of a monitor is never good. I don't know about the flyback. It may or may not be bad. After all, it did come on. If it hasn't been ran in a while, it might have something that was burning off of it. You did the right thing shutting it off.

That game has to be nearly 30 years old now, and by the look of old transformer, it hasn't been treated well either. If it were mine, it's time to at least replace all of the electrolytic capacitors in that thing. I don't know what they are, as I have never worked on that type of monitor before. Bob Roberts sells cap kits too, if he doesn't know what to send, some people on this forum will. You have a fighting chance that a cap kit will fix it since it showed a picture before you shut it down. See the caps keep all the power at the right level and frequency. Electrolytic caps are made with a wet paper over foil. They have a life expectancy because they dry out. And that life is not 30 years, more like 5 to 10. If they aren't working, all the power goes crazy and surges, etc. Circuits that are supposed to have 100 volts suddenly have 160.

Let me ask this, if you were to unplug the monitor power, turn the game on, does it coin up and play blind?
 
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Thanks for the quick response.

Yes the game will turn on and play blind. I can coin up... and play the game just no picture.

The first time I turned it on there was the smoke... It was on for less than a minute.. I didnt see smoke the second time I tried it but there was a metallic smell in the air.(left it on a couple mins but no change in the image on the monitor) The image that came up was jumbled looking and a very small square in the middle of the screen.

I should also add that I get neck glow now.

I order the cap kit with the isolation transformer so I have that already and will be installing.

What would cause the high pitch squealing? I have read that can be a flyback issue.. bob roberts actually has a post about it.

Other than a cap kit... can anyone shed light on how to continue to troubleshoot based on the symptoms?
 
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If it's showing a picture, it's working. That jumbled picture is probably what that board is producing, or you have your horizontal / vertical hold messed up. Putting in the cap kit is your next logical step to healing the monitor. That should fix a lot of it.

You might want to download or find a manual for that game and see if it has a "test" mode that will bring up a monitor test pattern. That will help you see if it's working.

If you want to know how to work on monitor, here's a guy that will take you through. I learned how to do it with this guy.

http://www.youtube.com/watch?v=YsZ5PJB-w2s&feature=related

He has a 4 part video, and they are each over an hour. It's really in-depth. If you intend to work on video games, Randy Fromm's arcade school is the place to start. He will go through all of it, and by the end of you will have a much better understanding of what you are dealing with and how to troubleshoot it and work on it.

I want to also add, I'm not an expert by any means. I've been working on video games for about 10 years, and I've fixed a few and I've scrapped a few too. Birdie King was one I scrapped. I think I have a birdie king2 board in a box somewhere because it didn't make the grade of "fixing" LOL. But this guy will show you what you need to know about all of the monitors and how to even read the schematics and understand them.
 
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Thanks for the input fredster! I have come across some Randy Fromm information and looked into the schooling (Its kinda pricey now... the vids anyways). The main purpose of this game is to use it as a learning tool... I have several games I have worked on but I am still learning! This forum and the people here have been a huge help!

I will check out the video you put in the link. I have been using these forums as well as research to learn how to "fish"... just trying to get some direction from everyone's experience.

I just worry about the smoke and what that can affect with the game as well as the squealing noise. I will keep searching the forums to come to a resolution. Even if I scrap the game.. maybe I can save the monitor... That would be worth it! Maybe I need to start a different thread associated with the squealing as this was more about my iso transformer... which is now fixed! Thanks!
 
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