Beginner Needs Some Help Interpreting Values From Schematics

whoamonga

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Howdy! I have clipped a part of a monitor schematic and was wondering if someone could help me understand some of the values on it. I have highlighted a few areas of the schematic and would like to ask...

1) C67 and C63 use J values instead of uF. They're also not-cylindrical electrolytic capacitors. Is the J value different than uF?

2) C59A doesn't specify 104uF, is that assumed, as it just read "104-100V". Same with C53

3) R101 simply says 120, so I'd assume 120ohm, but is there an assumed wattage implied?

I've also included photos of C67 and C63.

Thanks in advance for helping me along!schematics help.jpgimage1.jpegimage0.jpeg
 
Learn the cap codes:

capacitance-conversion-table.png


M398j.png
 
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The J is likely a tolerance code:


 
Those aren't electrolytics, and seldom go bad. Why do you think you need to replace them?
 
Howdy! I have clipped a part of a monitor schematic and was wondering if someone could help me understand some of the values on it. I have highlighted a few areas of the schematic and would like to ask...

1) C67 and C63 use J values instead of uF. They're also not-cylindrical electrolytic capacitors. Is the J value different than uF?

2) C59A doesn't specify 104uF, is that assumed, as it just read "104-100V". Same with C53

3) R101 simply says 120, so I'd assume 120ohm, but is there an assumed wattage implied?

I've also included photos of C67 and C63.

Thanks in advance for helping me along!View attachment 775340View attachment 775341View attachment 775342
For resistor wattage values, you generally find a note in the corner of the schematic which says "Resistance at 1/2 watt unless otherwise stated" or something similar.
 
Those aren't electrolytics, and seldom go bad. Why do you think you need to replace them?
Because I'm not skilled at troubleshooting quite yet and was looking to rebuild the entire vertical circuit to try and remedy the collapse.

I'd love to be in a place where I could just fine the components that are out of spec or malfunctioning, but not there yet. Also, in researching posts of vertical collapse with this particular chassis, someone mentioned C67 as a common culprit. 🤷‍♂️

I've been testing each component I remove thus far and sadly all have been in tolerance. Figure I'll keep digging.

Very thankful for all of the help, advice, questions, pointers I get from you guys.
 
Because I'm not skilled at troubleshooting quite yet and was looking to rebuild the entire vertical circuit to try and remedy the collapse.


Doing MORE work on a board when you're not skilled yet is the opposite of what you should be doing.


Also, you've been on this site for 16 years, 8 months, 3 days and you're just now learning? suspect.
 
Doing MORE work on a board when you're not skilled yet is the opposite of what you should be doing.


Also, you've been on this site for 16 years, 8 months, 3 days and you're just now learning? suspect.
Dang. Swinging right out the gate? Your prerogative man.

I'm not skilled in troubleshooting monitors, I can solder/desolder sufficiently enough to remove and replace components without damage, most the time.

As for how long I've enjoyed this community, why is that a factor in when I should know troubleshooting? In all that time I've raised kids, sold all my games, picked up new ones, gave up, got back into it, and here I am. Still learning and enjoying arcades without realizing my time limit was up...

You seem like a well respected dude around here, I'm just not sure what I did to deserve your unhelpful reply. Feel free to ignore any post of mine in the future, amigo.
 
Ignore the trolls, there are many here. Use the capability to ignore individual users.

My advice to you would be to post up whatever the specific problem you are having is. Often someone who is actually willing to help will emerge from the sea of trolls.

Most likely there are folks who can help you greatly narrow down your problem without looking at every component.

As stated previously, non-electrolytic caps rarely fail. Probably don't need to mess with those. Even electrolytic caps rarely seem to fail to the point of complete failure of a monitor.
Caps are a real boogie man in this hobby. Often when a "cap kit" "fixes" something, it's actually the rebuilding/reflowing that really fixed the issue.

Many monitors have flowcharts you can work through to isolate suspect components, have you searched for a flowchart for the monitor?
 
Ignore the trolls, there are many here. Use the capability to ignore individual users.
Thank you for the kind words and advice. Like, for real.

The monitor is a 25" Makvision M3125B1, and I actually had created a post on the monitor repair forum. The census was that this monitor is crappy, poorly manufactured, and so my first step actually should be a cap kit. I didn't take that as a half-hearted recommendation, but a legit move given this particular monitor.

I did reflow the entire board plus verify I hadn't created any shorts (following traces and checking neighboring joints), and swapped the vertical IC to no improvement. So, caps and this section are where my eyes are at.

Online information is a bit scarce on this guy, but what info I could find led me to that IC, and possibly C67.

Again, thank you guys for weighing in.
 

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The monitor is a 25" Makvision M3125B1
Not a chassis I'm familiar with so I can't provide any help. However, if you are seeing vertical collapse, you should make sure your yoke isn't shorted and that your yoke headers don't have any cold solder joints. Check continuity all the way from the bottom of the header to the back of the yoke, as well. Easy to at least rule this out.

I did read your other thread in the monitor repair section. If you heard any popping/sparks then you are in some trouble. One or several parts could be bad. And even if you found those bad part(s), it could be another component upstream causing the problem. Like finding a needle in a needle stack.

Best of luck getting it working. If you hit a brick wall, there are some people on here that repair chassis if you want to send it out.
 
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