Sanyo 20EZ Waves

barrysfarm

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I've got an almost fully restored donkey kong where one of the only things left to do is fix this annoying wave. It's slight. Maybe 2 millimeters up and down (left and right if in standard position). It probably doesn't bother anyone but me.

I purchased the monitor a few weeks ago, and the person I purchased it from said that it was recently capped.

We live in an old apartment, so i thought that maybe that might be the problem. The multimeter says that there are 124v going into the cabinet (at the power cord...before the psu). Does that sound about right?

The B+ reads ~90v. So this seems to be the problem.

The B+ adjustment seems to be glued so I can't adjust it. Also, any tool recommendation to adjust it? It's kind of a pain to reach.

I replaced the fuse on the monitor, because i shorted it out. Didn't seem to make a difference.

Also, I assembled this machine from parts after the cabinet was painted. I'm not sure where all the green ground wire should be touching. Could this be the problem?

I'm new to old monitors. I could probably perform a cap kip, but I may need a walkthrough. I do have soldering skills.
 
By frame screw do you mean the one that's by the chassis flyback? Or the one that's part of the thick steel frame that screws into the upper monitor support? or both.

I've got some similar small screw drivers at the office. I'll take some home with me.
 
I've seen machines with the ground running from the ISO up to the right side bolt that holds on the "thick steel frame" and splits off midstream from there and was screwed into a screw used for the flyback cage. You also want one running up to your control panel which is run up the right side of your cabinet (looking at it from the rear)

Bottom line - the more grounds the better.

And on a side note, the "wave" is very common and I'm suprised Dokert didn;t recommend his typical fix of "filter cap" ;)
The wave can also be caused by:
Electrical interference
No ground lead on power plug
bad caps on power supply
 
Alright. I'll attach the ground to wherever it looks like it should fit.

I forgot to say that I did replace the power plug because it didn't have a ground.

New to some of the terminology: ISO?
 
And on a side note, the "wave" is very common and I'm suprised Dokert didn;t recommend his typical fix of "filter cap" ;)
The wave can also be caused by:
Electrical interference
No ground lead on power plug
bad caps on power supply

You need to start with a good ground, and have proper B+ before you can even think about replacing the filter cap IMO.

Alright. I'll attach the ground to wherever it looks like it should fit.

I forgot to say that I did replace the power plug because it didn't have a ground.

New to some of the terminology: ISO?

The ground goes to the thick metal frame that attaches to the "L" bracket. It doesn't hurt to have a ground going to the chassis frame.

ISO = Isolation Transformer.
 
Now that the waves are gone, I've got another monitor problem.

I keep getting (what i think at least) is a horizontal collapse. Usually after I power on everything is working fine for a few minutes, and then everything collapses. It seems to come from the tiny bit of shaking while playing. A few times, the cabinet was on and working, and I pushed it back into place and when it hit the wall (softly, mind you) it collapsed. I've found that when it's collapsed I can get it to go back to normal if I rock the cabinet a specific way, but it only lasts until I play it again (usually about a day). The service switch on the chassis doesn't seem to fix it, though when I switch it, the line gets dimmer. Perhaps a cold solder joint?

Minus this issue, the game is playing fine. I can see that the game is still working, because the animations in the line match up to the sound effects.

I've had very little experience with monitors. I've never done a cap kit, and I haven't had the need to discharge yet. Still a little freaked out about it. I do have a bunch of experience soldering.
 

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Could this be the service switch on the monitor chassis? At least it's something easy to check. There is a white toggle switch in the middle of the chassis that if it's flipped you get something similiar to what you show in the picture. Check that switch. - Barry
 
Could this be the service switch on the monitor chassis? At least it's something easy to check. There is a white toggle switch in the middle of the chassis that if it's flipped you get something similiar to what you show in the picture. Check that switch. - Barry

It's not that. I've toggled the switch a few times and it makes the line dimmer.

Dokert; said:
Vertical Collapse

Alright. I'll check out TR402 & TR403. It sounds like cold solder points. Is there a tutorial out there on how to remove the chassis? I haven't done it before.
 
I discharged the monitor, pulled the chassis out and re-soldered the TR402 & TR403 pads. They definitely looked worn. Once everything was plugged back in, i took a breath and turned it on. There was about 2 seconds of what looked to be a collapse in the opposite direction... so horizontal collapse, i guess. But then it popped into place, and everything looked fine. I had to readjust the B+, but that part was easy.

It was the first time I discharged a monitor and pulled out a chassis. Totally not as bad as my mind made it out to be. I thought the discharge would be much louder and terrifying, but it totally wasn't. I laughed afterwards. It did take like 4 times with 15 min between each discharge.
 
I pulled the chassis out and didn't see anything strange around (what i think is the) HOT. Is the hot the bottlecap thing by where the flyback plugs into the chassis? If so, it only has 2 solder points to the chassis, unless I'm missing something.

Once i put the chassis back in, it worked fine for the night. I turned it on this morning, and it went back to how it was before. Single blue line running horizontally through the monitor. When I power on, there is a strange noise. Not really a static pop, but more like a 1/8 second of white noise or a ripping. Then after 20 or so seconds of the blue line, another pop, then the monitor turns off.

Seems I can't go a day without this monitor doing something wrong.

Here's a photo:
 

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I pulled the chassis out and didn't see anything strange around (what i think is the) HOT. Is the hot the bottlecap thing by where the flyback plugs into the chassis? If so, it only has 2 solder points to the chassis, unless I'm missing something.

Yes, that is the HOT.

Reflow the solder for the HOT, if that doesn't cure the problem replace the HOT.
 
It looks like the HOT needs to be replaced. The solder points that lead to it have been reflowed, I checked to make sure the wires still connected to the HOT, and I tested the HOT and I still have the same problem.

I ordered a new one and it should be on it's way.

Do you think I'll need to replace the flyback? If so, I'll order it.
 
I replaced the HOT. Same problem, though after a bit of adjusting on the pots, the line isn't just blue. It's got red and green in it.

I went ahead and ordered a flyback. Should I replace it?
 
I replaced the flyback as well as doing a deluxe cap kit tonight. No change what-so-ever. Starting to pull my hair out. This is getting really frustrating.

The B+ voltage is at 108.

So far:

New flyback
Deluxe cap kit
Replaced HOT

Here are some photos. I can tell the game plays in the line.
 

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