mhanlen1
New member
Donkey Kong Cocktail Repair Log - Tracking Down Image Shift
So DK is my first cab, and so far it's teaching me a lot about arcade repair. I'm a newcomer to arcade collecting, so this thread should be read with that in mind. Before finding my cab at a thrift store, I had never soldered, or looked inside an arcade machine before. I do have a background in A/V, but not in repair side, so I'm learning about electronic components and arcade parts as I go. Anyway I'm creating this repair log in an effort to track down a video issue I have. Hopefully if I ever find the cause, this thread will help others who may be experiencing the same thing. Here is a video of the problem.
In order to track down the screen shift that my cab has been experiencing I started by capping my monitor. A few months ago I purchased Bob Roberts standard cap kit for a Sanyo 20EZ. I purchased this for the primary purpose of correcting a screen fold. The kit fixed the screen fold, but didn't fix the image shift problem. Here are the caps that came with Bobs kit, to use as a reference to those who haven't ordered it.
1uf50v___________C302/C453
1uf250v__________C408/C467
10uf50v__________C301/C303/C406
10uf250v_________C407/C471
22uf50v__________C464
47uf10/16v________C458
100uf16/25v_______C459
100uf160v________C410/C472
220uf25v_________C469
330uf25/50v______ C468
None of the above caps are Bi-polar (or NP as they're labeled on the Sanyo board), so it's important to mind where the "+" and "–" go.
So after installing the kit, I still had an image shift. I then ordered some replacement pots for my game PCB and the Sanyo monitor both. They were sensitive to the touch, so I figured they should be replaced anyway. After replacing those, the pots were no longer so touchy, but it didn't resolve the image shift.
It was then recommended to replace C606 with is the filter cap for the B+, and it may solve it. Well since Bob's regular kit didn't include all the monitor caps, I found a complete list Dokert created for mouser in this thread (which doesn't include the C606- by the way). So for the sake of covering all my bases I ordered a C606, the hi-temp monitor cap list, and the audio cap kit (which I also didn't do the 1st time). I also tore down my PP7b power supply and made a list of all the caps I need for it, just in case. So yesterday I got all the monitor caps and power supply caps in.
My first order of business was to install all the caps that didn't come with Bob's Kit, and the C606, and the audio board (a preventative measure even though I have no sound problems). So now all the caps on the Sanyo monitor are brand new. Here are the additional ones I installed yesterday (minus the audio kit).
470uf160v____________C606
220uf16v_____________C202
1uf50v_______________C454/C166
220uf16v_____________C161
1uf160v______________C610
4.7uf25v______________C411/C462 (both of these caps are Bi-polar- the only 2 B.P. caps on the monitor)
470uf10v_____________C609
So after all of this, I still have the video problem. This would leave me to believe it's not a monitor cap issue. Despite the problem I don't regret installing the additional caps, because it improved overall brightness and made the colors richer. If I could do it again, had I would have known better, I'd have ordered a complete cap kit for the audio and video. It's really worth it to replace them all at once.
So what's next? First I'm going to reattempt adjusting my B+ after not getting any reading on it last time I had the cab apart. I think my problem is using a multimeter that isn't functioning properly. It also doesn't help that I've never used a multimeter before this project.
Once I tackle the B+, I'm tearing apart my power supply and recapping it (within the next day or two). Anyway I'll keep track of my progress here, as a help to others who have this same annoying problem.
It would be nice to have a spare board set, monitor, or power supply lying around to help isolate the issue, but I don't have that luxury. At least I'm learning more this way.
OK, I'm off to radio shack…
So DK is my first cab, and so far it's teaching me a lot about arcade repair. I'm a newcomer to arcade collecting, so this thread should be read with that in mind. Before finding my cab at a thrift store, I had never soldered, or looked inside an arcade machine before. I do have a background in A/V, but not in repair side, so I'm learning about electronic components and arcade parts as I go. Anyway I'm creating this repair log in an effort to track down a video issue I have. Hopefully if I ever find the cause, this thread will help others who may be experiencing the same thing. Here is a video of the problem.
In order to track down the screen shift that my cab has been experiencing I started by capping my monitor. A few months ago I purchased Bob Roberts standard cap kit for a Sanyo 20EZ. I purchased this for the primary purpose of correcting a screen fold. The kit fixed the screen fold, but didn't fix the image shift problem. Here are the caps that came with Bobs kit, to use as a reference to those who haven't ordered it.
1uf50v___________C302/C453
1uf250v__________C408/C467
10uf50v__________C301/C303/C406
10uf250v_________C407/C471
22uf50v__________C464
47uf10/16v________C458
100uf16/25v_______C459
100uf160v________C410/C472
220uf25v_________C469
330uf25/50v______ C468
None of the above caps are Bi-polar (or NP as they're labeled on the Sanyo board), so it's important to mind where the "+" and "–" go.
So after installing the kit, I still had an image shift. I then ordered some replacement pots for my game PCB and the Sanyo monitor both. They were sensitive to the touch, so I figured they should be replaced anyway. After replacing those, the pots were no longer so touchy, but it didn't resolve the image shift.
It was then recommended to replace C606 with is the filter cap for the B+, and it may solve it. Well since Bob's regular kit didn't include all the monitor caps, I found a complete list Dokert created for mouser in this thread (which doesn't include the C606- by the way). So for the sake of covering all my bases I ordered a C606, the hi-temp monitor cap list, and the audio cap kit (which I also didn't do the 1st time). I also tore down my PP7b power supply and made a list of all the caps I need for it, just in case. So yesterday I got all the monitor caps and power supply caps in.
My first order of business was to install all the caps that didn't come with Bob's Kit, and the C606, and the audio board (a preventative measure even though I have no sound problems). So now all the caps on the Sanyo monitor are brand new. Here are the additional ones I installed yesterday (minus the audio kit).
470uf160v____________C606
220uf16v_____________C202
1uf50v_______________C454/C166
220uf16v_____________C161
1uf160v______________C610
4.7uf25v______________C411/C462 (both of these caps are Bi-polar- the only 2 B.P. caps on the monitor)
470uf10v_____________C609
So after all of this, I still have the video problem. This would leave me to believe it's not a monitor cap issue. Despite the problem I don't regret installing the additional caps, because it improved overall brightness and made the colors richer. If I could do it again, had I would have known better, I'd have ordered a complete cap kit for the audio and video. It's really worth it to replace them all at once.
So what's next? First I'm going to reattempt adjusting my B+ after not getting any reading on it last time I had the cab apart. I think my problem is using a multimeter that isn't functioning properly. It also doesn't help that I've never used a multimeter before this project.
Once I tackle the B+, I'm tearing apart my power supply and recapping it (within the next day or two). Anyway I'll keep track of my progress here, as a help to others who have this same annoying problem.
It would be nice to have a spare board set, monitor, or power supply lying around to help isolate the issue, but I don't have that luxury. At least I'm learning more this way.
OK, I'm off to radio shack…
Last edited:


