TokensArcade
Member
Hello KLOV:
I recently acquired a Red Tent w/ Vs. Tennis on it that I bought as a project. It has a number of issues with both monitors and while I've made good progress so far, there's still plenty more to figure out and I'd like a bit of help. Note that for this diagnosis process I have been using a CGA Test Pattern Generator for video signal and a Donkey Kong Cocktail for a 100 V Power source (with all of the Donkey Kong related things unplugged).
MONITOR 1:
This monitor was vertically collapsed when I got it and after doing some tests of I601 I checked the resistor R625 and Diode D603 as instructed in the Nintendo troubleshooting guide for the monitor. They seemed to test out fine, but i replaced them anyways just to be safe, as well as reflowed some (but not all) of the points on the board. While I couldn't find a broken connection, some joints did look questionable. I was able to get rid of the collapse and now I have what you see in the attached picture.
As you can see, it's far better, but not there yet. The image is curved to the right and there's lines across the image. The lines move when I adjust the vertical hold and the curves change a bit when I adjust the horizontal hold. The best I can get is a stable, but warped pic. It also seems to be more stable on some patterns than others. I should note that it appears that the previous owner capped the monitor, though I can't say for certain if they did it right.
What would be the next step to diagnosing this monitor?
MONITOR 2:
This monitor was working fine, with the exception of no sound. However, I removed it too when I took out Monitor 1 just to give it a better look. After getting Monitor 1 to no longer collapse, I decided to test the Test Pattern Generator on this monitor, just to see if the lines or curves were caused by the generator. However, upon powering Monitor 2 up in the same way as Monitor 1, the warm-up crackling started then stopped abruptly on power-up and I had no video signal. Upon powering it up again I got the same thing, but this time I saw an arc in the tube. I have not gotten this thing to turn on properly since.
Despite the arc I DID NOT see any smoke or smell anything burning. This monitor, as far as I can tell, has NOT been capped or worked on much during it's life. This monitor was also INCREDIBLY filthy, much more so than Monitor 1, further backing up my suspicion that this monitor has not been worked on while the other one has. I know that arcing in the tube is often associated with a bad flyback, so I visually inspected the filthy flyback, but couldn't find any major meltdowns or holes (That being said, it's hard to look at them since I can't fully remove the cover without cutting wires).
One other thing worth noting is that before I got replacement keys for the red tent, this monitor did have an episode where it didn't power on until the third or so try, while the collapsed Monitor 1 did turn on. I have a feeling that's no coincidence.
Should I try getting a new flyback? Could it possibly be a B+ issue? If this is a Flyback issue, could the HOT also be jeopardized?
I welcome any advice you may have on fixing these two monitors.
Thank you very much and have a good day!
I recently acquired a Red Tent w/ Vs. Tennis on it that I bought as a project. It has a number of issues with both monitors and while I've made good progress so far, there's still plenty more to figure out and I'd like a bit of help. Note that for this diagnosis process I have been using a CGA Test Pattern Generator for video signal and a Donkey Kong Cocktail for a 100 V Power source (with all of the Donkey Kong related things unplugged).
MONITOR 1:
This monitor was vertically collapsed when I got it and after doing some tests of I601 I checked the resistor R625 and Diode D603 as instructed in the Nintendo troubleshooting guide for the monitor. They seemed to test out fine, but i replaced them anyways just to be safe, as well as reflowed some (but not all) of the points on the board. While I couldn't find a broken connection, some joints did look questionable. I was able to get rid of the collapse and now I have what you see in the attached picture.
As you can see, it's far better, but not there yet. The image is curved to the right and there's lines across the image. The lines move when I adjust the vertical hold and the curves change a bit when I adjust the horizontal hold. The best I can get is a stable, but warped pic. It also seems to be more stable on some patterns than others. I should note that it appears that the previous owner capped the monitor, though I can't say for certain if they did it right.
What would be the next step to diagnosing this monitor?
MONITOR 2:
This monitor was working fine, with the exception of no sound. However, I removed it too when I took out Monitor 1 just to give it a better look. After getting Monitor 1 to no longer collapse, I decided to test the Test Pattern Generator on this monitor, just to see if the lines or curves were caused by the generator. However, upon powering Monitor 2 up in the same way as Monitor 1, the warm-up crackling started then stopped abruptly on power-up and I had no video signal. Upon powering it up again I got the same thing, but this time I saw an arc in the tube. I have not gotten this thing to turn on properly since.
Despite the arc I DID NOT see any smoke or smell anything burning. This monitor, as far as I can tell, has NOT been capped or worked on much during it's life. This monitor was also INCREDIBLY filthy, much more so than Monitor 1, further backing up my suspicion that this monitor has not been worked on while the other one has. I know that arcing in the tube is often associated with a bad flyback, so I visually inspected the filthy flyback, but couldn't find any major meltdowns or holes (That being said, it's hard to look at them since I can't fully remove the cover without cutting wires).
One other thing worth noting is that before I got replacement keys for the red tent, this monitor did have an episode where it didn't power on until the third or so try, while the collapsed Monitor 1 did turn on. I have a feeling that's no coincidence.
Should I try getting a new flyback? Could it possibly be a B+ issue? If this is a Flyback issue, could the HOT also be jeopardized?
I welcome any advice you may have on fixing these two monitors.
Thank you very much and have a good day!

