Olympus OEV203 full recap

[HermanMunster]

I am more than half way done replacing all capacitors in my 2003 Olympus OEV203. The new caps on the power suply board have longer lives and higher ripple current ratings than the original ones. However, some of the smaller caps on the A board that I have replaced (10uf 50v, 4.7uf 50v, 47uf) have longer lives than the original ones, but lower ripple current ratings. Do you think that having lower ripple current ratings on these smaller caps could become an issue in the future? I am mostly replacing Rubycons YK with Nichicons LD which in comparison have 10k hour lives vs. 2k hour lives on the YK. However, ripple current ratings on YKs are in some cases twice of that of the LDs.

[BazookaBen]

I've never heard from anyone that replacing the smaller caps on a PVM is necessary. It's usually only the caps near heatsinks in the power supply and deflection section that start to go bad.

Like, I think it was Retro Tech on youtube that tested some of the smaller caps he pulled out of a PVM and they were all still holding their specified capacitance. I imagine there are a couple more decades of life left in those

So I know you've probably already bought, like what, 200 caps? You should probably just replace the high voltage ones and see how it looks before you start replacing the rest.

[HermanMunster]

Hi, thanks for your reply! I am trying to do what this guy from the UK did:
https://www.retrogameboards.com/t/honey ... -log/852/3

He said that the quality of the picture increased considerably after replacing all of them. I'm more than half way through and have already taken the whole thing apart, so I might as well just replace them all. Just want to know if the lower ripple current rating on smaller caps could become an issue.

Thanks!

[BazookaBen]

Did your Olympus have "streaking" after bright colors?

Where after a really bright element on the screen, there is a streak of slightly darker color the right of it? My OEV203 currently has that to a small degree. So I've been wondering what specifically I should recap on it to help with that.

[jd213]

I don't think it matters for PVMs:
https://www.youtube.com/watch?v=URAqjvH3m1w

Doing the caps on the input board is some serious dedication though. I wonder if that was really necessary, I don't think I've seen anyone else recommend it.

[HermanMunster]

I do have some slight color purity issues on the top right and bottom right of the PVM that I have not been able to fix not even with my professional degaussing tool. Upon closer inspectioninside the shell, I realized that there are two small magnets placed on the opposite side of the crt on the back of the tube. I wonder if removing those two magnets would make the issue on the other side go away, or make it worse.

I also do have some very slight vertical jailbars (only about 3 of them) on the right side of the screen (not coming from any of my consoles; 100% sure about this) that I was hoping a capacitor replacement would take care of them as well.

I am doing a full recap, including the input board which requires miniature caps and a lot of desoldering. I bought high quality 3k hour miniature nichicon capacitors for this board.

In total, I spent about $130 usd in capacitors.

Thanks for the clarification on ripple current, this is what I needed to know! Haha thankfully I don't need to buy more capacitors for this pvm.

If everything goes well with this one, and I see noticeable improvements, I will do a full recap on my other PVM; a 1953MD which has very low usage and is in mint condition. For the smaller caps on that monitor I am planning on using Panasonic FR series instead of the nichicons LD.

[tongshadow]

Doing the caps on the input board is some serious dedication though. I wonder if that was really necessary, I don't think I've seen anyone else recommend it.

On the L4/L5 models there's an issue where you get different white color balance between RGB/Component due to capacitors going bad on the input processing board (B-Board). Said capacitors are also close to heat sources on this specific model.

That said, I would only change bad capacitors. Nothing good comes out of replacing good parts and it's very difficult to find quality capacitors comparable to the ones found in PVMs.

[NewSchoolBoxer]

I don't think it matters for PVMs:
https://www.youtube.com/watch?v=URAqjvH3m1w

Doing the caps on the input board is some serious dedication though. I wonder if that was really necessary, I don't think I've seen anyone else recommend it.

I don't mean to sound elitist or brag but I have an electrical engineering degree and that video was cringe to watch. At least he admits his mistake. I doubt most notable Tubers I would ever do such a thing. Sometimes I think we shouldn't allow people to teach themselves electronics on the internet with anything above 5V but I don't give money to politicians.

So electrolytic capacitors have ripple current ratings in their datasheets. Check out the datasheet to the solid electrolytics I just bought. Can see maximum ripple currents specified on page 2. Very high values. A 6.3V 220uF isn't getting more than 2980mArms (3A) of ripple riding on a DC voltage or your circuit is already destroying itself. The interesting part is the frequency of the ripple matters. The ~3A is for 100+ kHz ripple. 120 Hz ripple, which is what it is in the US power supply after rectification, has a correction factor of 0.05. This means the max ripple is 20x less, or ~150mArms. That could definitely happen from an antique and uncapped power supply.

What if we have 100mA ripple at 120 Hz and 300mA at 150 kHz? Apply correction factor and take sum of squares. Effective ripple is sqrt[(0.100/0.05)^2 + (0.300/1)^2] = ~2A of ripple so we're under 3A and doing alright.

But why is there a ripple rating anyway? Electrolytics have significant ESRs and the I^R losses from that cause them to heat up and this excess heat reduces their lifespan significantly. Classic formula for liquid electrolytics is life cut in half for every 10°C above ambient. Solids are more tolerant and don't dry out but they have tradeoffs such as cost and lower ESR is worse in certain cases.

I am more than half way done replacing all capacitors in my 2003 Olympus OEV203. The new caps on the power suply board have longer lives and higher ripple current ratings than the original ones. However, some of the smaller caps on the A board that I have replaced (10uf 50v, 4.7uf 50v, 47uf) have longer lives than the original ones, but lower ripple current ratings. Do you think that having lower ripple current ratings on these smaller caps could become an issue in the future? I am mostly replacing Rubycons YK with Nichicons LD which in comparison have 10k hour lives vs. 2k hour lives on the YK. However, ripple current ratings on YKs are in some cases twice of that of the LDs.

10k hours, nice, I would have gone with 5K or above. Yeah half the maximum ripple current as before I'm not remotely concerned about when you also recapped the whole power supply. At the hottest parts, I'd consider upping the voltage rating if you have space since the larger volume gives the caps more space to dissipate heat. In other words, they run cooler and get derated less.

But...I'm with everyone else and would not recommend proactively recapping a 14" or larger CRT. My 20" has about 500 and if I screw up and solder bridge 1% of the time, odds aren't looking good. Recapping just the power and deflection parts, that sounds like good advice.

Hi, thanks for your reply! I am trying to do what this guy from the UK did:
https://www.retrogameboards.com/t/honey ... -log/852/3

He said that the quality of the picture increased considerably after replacing all of them. I'm more than half way through and have already taken the whole thing apart, so I might as well just replace them all. Just want to know if the lower ripple current rating on smaller caps could become an issue.

Thanks!

What I think is either the picture quality didn't and he imagined it, or it did just due to replacing the power and deflection sections and the rest did nothing. Circuits run better with low ripple power. As a parallel, audio world has outrageously expensive silver cables and rhodium connectors, despite the low kHz range, that people claim make their music sound better, claims that fail with double blind testing.

And you know, even with my education and experience, I can still make a mistake or misread a datasheet. Doesn't happen with the fundamentals.

[HermanMunster]

I don't think it matters for PVMs:
https://www.youtube.com/watch?v=URAqjvH3m1w

Doing the caps on the input board is some serious dedication though. I wonder if that was really necessary, I don't think I've seen anyone else recommend it.

I don't mean to sound elitist or brag but I have an electrical engineering degree and that video was cringe to watch. At least he admits his mistake. I doubt most notable Tubers I would ever do such a thing. Sometimes I think we shouldn't allow people to teach themselves electronics on the internet with anything above 5V but I don't give money to politicians.

So electrolytic capacitors have ripple current ratings in their datasheets. Check out the datasheet to the solid electrolytics I just bought. Can see maximum ripple currents specified on page 2. Very high values. A 6.3V 220uF isn't getting more than 2980mArms (3A) of ripple riding on a DC voltage or your circuit is already destroying itself. The interesting part is the frequency of the ripple matters. The ~3A is for 100+ kHz ripple. 120 Hz ripple, which is what it is in the US power supply after rectification, has a correction factor of 0.05. This means the max ripple is 20x less, or ~150mArms. That could definitely happen from an antique and uncapped power supply.

What if we have 100mA ripple at 120 Hz and 300mA at 150 kHz? Apply correction factor and take sum of squares. Effective ripple is sqrt[(0.100/0.05)^2 + (0.300/1)^2] = ~2A of ripple so we're under 3A and doing alright.

But why is there a ripple rating anyway? Electrolytics have significant ESRs and the I^R losses from that cause them to heat up and this excess heat reduces their lifespan significantly. Classic formula for liquid electrolytics is life cut in half for every 10°C above ambient. Solids are more tolerant and don't dry out but they have tradeoffs such as cost and lower ESR is worse in certain cases.

I am more than half way done replacing all capacitors in my 2003 Olympus OEV203. The new caps on the power suply board have longer lives and higher ripple current ratings than the original ones. However, some of the smaller caps on the A board that I have replaced (10uf 50v, 4.7uf 50v, 47uf) have longer lives than the original ones, but lower ripple current ratings. Do you think that having lower ripple current ratings on these smaller caps could become an issue in the future? I am mostly replacing Rubycons YK with Nichicons LD which in comparison have 10k hour lives vs. 2k hour lives on the YK. However, ripple current ratings on YKs are in some cases twice of that of the LDs.

10k hours, nice, I would have gone with 5K or above. Yeah half the maximum ripple current as before I'm not remotely concerned about when you also recapped the whole power supply. At the hottest parts, I'd consider upping the voltage rating if you have space since the larger volume gives the caps more space to dissipate heat. In other words, they run cooler and get derated less.

But...I'm with everyone else and would not recommend proactively recapping a 14" or larger CRT. My 20" has about 500 and if I screw up and solder bridge 1% of the time, odds aren't looking good. Recapping just the power and deflection parts, that sounds like good advice.

Hi, thanks for your reply! I am trying to do what this guy from the UK did:
https://www.retrogameboards.com/t/honey ... -log/852/3

He said that the quality of the picture increased considerably after replacing all of them. I'm more than half way through and have already taken the whole thing apart, so I might as well just replace them all. Just want to know if the lower ripple current rating on smaller caps could become an issue.

Thanks!

What I think is either the picture quality didn't and he imagined it, or it did just due to replacing the power and deflection sections and the rest did nothing. Circuits run better with low ripple power. As a parallel, audio world has outrageously expensive silver cables and rhodium connectors, despite the low kHz range, that people claim make their music sound better, claims that fail with double blind testing.

And you know, even with my education and experience, I can still make a mistake or misread a datasheet. Doesn't happen with the fundamentals.

Thanks for your reply! Yes, I agree, the video also made me cringe a bit even though I am not an electrical engineer and just doing this as a hobby. A quick search on google would tell you what the ripple current rating on a capacitor is and would have prevented him from making the mistake.

Anyway, one of the reasons the LD capacitors that I am using have lower ripple current ratings than the ones I replaced, is surprisingly because I bought higher voltage capacitors thinking that they would have higher ripple current ratings than the same capacitors with the original voltage ratings. Here is an example, the 10uf 50v Nichicons LD capacitors have a life of 10k hours and a ripple current at high frequency of 90 miliamps. The 63v version of the same capacitor has the same size, same life, but a ripple current rating at high frequency of only 80 miliamps.

However, I was very careful when I selected the larger voltage and larger capacitance capacitors. I made sure that I chose a high life, higher voltage in most cases, and as high as ripple current rating I could get. I certainly did not cut any corners there.

There are roughly about 190 caps on this pvm. It doesn't really bother me to continue to replace them all, an I am being super careful. So far I have not even lifted a single trace, and I have been replacing them one by one.

Anyway, thanks for that reply. I knew that I could take care of most of the ripple current issues by using good capacitors on the power supply board and deflection circuits, but I was not sure if other parts of the A board with smaller caps were also subject to ripple currents generated by other components.?.?

[HermanMunster]

Here is the power supply board with the new caps installed. Note that I had to bend one cap slightly forward for it to fit under the metal shield that goes on top:


https://ibb.co/Tw70yCp