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friedpotatoz

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Hello everyone,

So long story short, I had a working chassis that had a green tint so I decided to recap it. That has been done along with replacing the HOT. I turn it on and I get no neck glow, no static on the monitor and I hear a whistle coming from the chassis. Has anyone ever come across this? Not sure what else to do or replace. I've read that these chassis fly backs almost never go bad, so what else could it be?

After I recapped it I noticed I needed a bipolar cap for one of the caps, replaced that as well. Video: https://flic.kr/p/WLX1v5

any help is appreciated.

-John V.
 
Indeed there is 1 bipolar cap on the MS9 chassis.
Have you re-checked all other caps for polarity and solder joints?
 
Why did you replace the HOT? Is the replacement you got a genuine part and not a cheap Chinese knock off?

Honestly, I would put the old one back in if you're unsure.
 
I agree with Pascal, doublecheck polarity and solder joints first. Especially in the power area of the chassis.
 
Why did you replace the HOT? Is the replacement you got a genuine part and not a cheap Chinese knock off?

Honestly, I would put the old one back in if you're unsure.
This...
I've learned to never replace the HOT unless it's actually bad. I've been burned 3 times with replacement HOTs that were faulty or DOA when the original would have been just fine.

There's other stuff that can go wrong when replacing them too, generally they need to be electrically isolated from the heat sync they're attached to so you need to make sure you're using a non-conductive thermal paste.

------------

Many chassis have a flyback protection circuit that will shut it down if there is a problem with the HOT, no neck glow means that the flyback is inactive... however the high pitched sound indicate that's that there's a high frequency signal somewhere.
 
I have but I am going to give it a 3rd check on each cap just to make sure. I turned it on not knowing at the time that I needed a bipolar cap plus one of the caps that was in my cap kit was wrong, the wrong UF from a few cap lists i found online. Never buying from Johns arcade again.
Indeed there is 1 bipolar cap on the MS9 chassis.
Have you re-checked all other caps for polarity and solder joints?
Just reading online and people have swapped the HOT, how would I know if its not working correctly? I still have the original.
Why did you replace the HOT? Is the replacement you got a genuine part and not a cheap Chinese knock off?

Honestly, I would put the old one back in if you're unsure.
Yeah that makes sense, I didn't know that I will make sure to grab some paste. So a bad cap or wrong placed cap would cause this whistling sound? It made the sound before I swapped the hot. Thanks for the help guys!
This...
I've learned to never replace the HOT unless it's actually bad. I've been burned 3 times with replacement HOTs that were faulty or DOA when the original would have been just fine.

There's other stuff that can go wrong when replacing them too, generally they need to be electrically isolated from the heat sync they're attached to so you need to make sure you're using a non-conductive thermal paste.
 
I know it's a bit late now, but never buy ready-made capkits. There are several revisions of the MS9, which are all slightly different. There wasn't any capkit to match my MS9 100%, so I took all caps off and made a schematic of it myself, then ordered the caps and soldered the new ones in place. Really hope you will get it working again.
 
Just reading online and people have swapped the HOT, how would I know if its not working correctly? I still have the original.
There was nothing wrong with the original. You had a working picture, didn't you? A green tint could be caused by a bad pot, bad capacitor, bad diode, bad resistor, bad monitor, any number of things really, but not a blown HOT.
 
yeah for something like green tint my first step would be cap kit only, and then if that didn't fix it, check the color pots and failing that a tube rejuvenation. Worst case the gun in the tube went bad...


I know this advice is too late but for anyone else doing a cap kit.
I've bought many cap kits and and I've never installed one that was 100% exact. I still buy them though and they're fine as long as the caps are high temp name brand caps.

When I do a cap kit I remove then replace one cap at a time in order of the PCB silkscreen number. With each I do the following.
1. I separate out the cap to be installed from the pile.
2. I verify that the polarity of the installed cap matches the polarity of the silkscreen matches the polarity on the cap map that I have. I verify that the new cap. if there is a difference I note it on the cap map in red marker. Even if verified correct I put a check mark on the cap map.
3. I verify that the farad and voltage rating of the old cap matches the new cap, matches the cap list. if there is any variation at all I note it on the cap list I'm using. if verified correct I put a check mark next to the cap on the cap list.
4. Only after the above checks are complete do I remove the old cap. if the farads on the new cap don't match the old cap I don't install the new cap, if the voltages are different I only install the new cap if the voltage rating is the same or higher than the old cap. if the voltages on the new cap match the cap list but the old cap is higher than the new cap then I look for evidence that a cap kit has been done before and triple check my research on the cap values and chassis variations.. sometimes it's a judgement call, somtimes I'll just leave the old cap if it's a smaller one and doesn't look bad. or I'll source a higher voltage replacement.
5. once the new cap is installed I double check the polarity against the silkscreen and my notes. and I put a second check mark on the cap list to note that it's been installed... if not installed I write out "NOT INSTALLED"

there have been more than a few cap kits I've done where I left 1 or 2 old caps in place because of the new cap not matching and the old cap looked good and unimportant and I didn't have time to source a proper replacement.

When installing caps any list or maps, and even the silkscreen are just reference... the old cap values and polarity are GOSPEL. Because sometimes even the silkscreen is wrong and no one is infallible so mistakes can exists in cap lists and cap maps.... the reason the old caps take presidence over everything else is because they were installed when the monitor was working... meaning that no matter what anything else says, they represent a working, verified configuration. Not to mention, maybe your chassis is a different revision that uses slightly different components... OLD CAPS ARE GOSPEL

By documenting any variations, no matter how subtle if there is any deviation or conflicting information, I have it clearly documented. and forced myself to triple check every cap and document exactly which caps were installed or which caps were either left out of the kit or that I opted not to install.

----------
I only install other components on an as-needed basis. And I install them separately from the cap kit. cap kit first and then test, then if it's still not functioning, then pull the chassis again and troubleshoot further.
 
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I see that now, still new to monitor fixing. I have already taken off all of the caps in the list so that was my first mistake. I guess I have to start over.
I know it's a bit late now, but never buy ready-made capkits. There are several revisions of the MS9, which are all slightly different. There wasn't any capkit to match my MS9 100%, so I took all caps off and made a schematic of it myself, then ordered the caps and soldered the new ones in place. Really hope you will get it working again.
I get your point, I will put back the original hot.
There was nothing wrong with the original. You had a working picture, didn't you? A green tint could be caused by a bad pot, bad capacitor, bad diode, bad resistor, bad monitor, any number of things really, but not a blown HOT.
Well that's a long story about the current monitor on my astro. I actually used a tube rejuvenator and fu*ked it up, totally went black no picture no neck glow. So I had another tube from my old broken neo29 and used that monitor, so for sure I know its not the monitor. Again it was working fine with just that green tint, but now after the capkit i get no current going to the tube. Thanks for the info on how to properly install these things.

Now that I have done this, what would be the best thing to do now. Should I go through each one and double check polarity plus uf matching? Is there a list I could reference? I was using 300wins list after the fact, before I knew that these kits would vary. Also wheres the best place to buy caps?

So for now im going to put back that original hot, and maybe buy some more caps. Should i post a pic of my chassis to see what exact model it is?

Thanks again for the help guys.
yeah for something like green tint my first step would be cap kit only, and then if that didn't fix it, check the color pots and failing that a tube rejuvenation. Worst case the gun in the tube went bad...


I know this advice is too late but for anyone else doing a cap kit.
I've bought many cap kits and and I've never installed one that was 100% exact. I still buy them though and they're fine as long as the caps are high temp name brand caps.

When I do a cap kit I remove then replace one cap at a time in order of the PCB silkscreen number. With each I do the following.
1. I separate out the cap to be installed from the pile.
2. I verify that the polarity of the installed cap matches the polarity of the silkscreen matches the polarity on the cap map that I have. I verify that the new cap. if there is a difference I note it on the cap map in red marker. Even if verified correct I put a check mark on the cap map.
3. I verify that the farad and voltage rating of the old cap matches the new cap, matches the cap list. if there is any variation at all I note it on the cap list I'm using. if verified correct I put a check mark next to the cap on the cap list.
4. Only after the above checks are complete do I remove the old cap. if the farads on the new cap don't match the old cap I don't install the new cap, if the voltages are different I only install the new cap if the voltage rating is the same or higher than the old cap. if the voltages on the new cap match the cap list but the old cap is higher than the new cap then I look for evidence that a cap kit has been done before and triple check my research on the cap values and chassis variations.. sometimes it's a judgement call, somtimes I'll just leave the old cap if it's a smaller one and doesn't look bad. or I'll source a higher voltage replacement.
5. once the new cap is installed I double check the polarity against the silkscreen and my notes. and I put a second check mark on the cap list to note that it's been installed... if not installed I write out "NOT INSTALLED"

there have been more than a few cap kits I've done where I left 1 or 2 old caps in place because of the new cap not matching and the old cap looked good and unimportant and I didn't have time to source a proper replacement.

When installing caps any list or maps, and even the silkscreen are just reference... the old cap values and polarity are GOSPEL. Because sometimes even the silkscreen is wrong and no one is infallible so mistakes can exists in cap lists and cap maps.... the reason the old caps take presidence over everything else is because they were installed when the monitor was working... meaning that no matter what anything else says, they represent a working, verified configuration. Not to mention, maybe your chassis is a different revision that uses slightly different components... OLD CAPS ARE GOSPEL

By documenting any variations, no matter how subtle if there is any deviation or conflicting information, I have it clearly documented. and forced myself to triple check every cap and document exactly which caps were installed or which caps were either left out of the kit or that I opted not to install.
 
I know it's a bit late now, but never buy ready-made capkits. There are several revisions of the MS9, which are all slightly different. There wasn't any capkit to match my MS9 100%, so I took all caps off and made a schematic of it myself, then ordered the caps and soldered the new ones in place. Really hope you will get it working again.
I bet others would find it helpful if you were to create a thread with your specific MS9 variant and schematic/cap list.

Just a thought if you find the time! :)
 
I know it's a bit late now, but never buy ready-made capkits. There are several revisions of the MS9, which are all slightly different. There wasn't any capkit to match my MS9 100%, so I took all caps off and made a schematic of it myself, then ordered the caps and soldered the new ones in place. Really hope you will get it working again.
I bet others would find it helpful if you were to create a thread with your specific MS9 variant and schematic/cap list.
Just a thought if you find the time! :)
That's exactly the point I am trying to make, don't follow somebody else's guide or caplist. Just take yours off, note down the values, order your caps and solder them on.

The only reason you wouldn't do this is if you are in a hurry and want to order the caps in advance so you can do it all in an afternoon/evening/day. But trust me, you're better off sticking to doing it my/twistedsymphony's way... :)
 
So for now im going to put back that original hot, and maybe buy some more caps. Should i post a pic of my chassis to see what exact model it is?
Posting some detailed pics of your chassis would be good to identifying the exact revision. IIRC there are at least 5 variants (maybe more) of the MS9-29 and it's possible that the cap list is different between them.

MS9-29A (Astro chassis variant with manual degauss)
MS9-29N (Namco maybe?)
MS9-29T (Taito chassis variant with auto degauss)
MS9-29S (I don't know where this one was used)
MS9-29SU (Sega Universal chassis variant, designed for Hitachi tube, found in Twin units and other Sega machines)

Now that I have done this, what would be the best thing to do now. Should I go through each one and double check polarity plus uf matching? Is there a list I could reference? I was using 300wins list after the fact, before I knew that these kits would vary.
There's a cap list on AO: http://wiki.arcadeotaku.com/w/Nanao_MS-9_capacitor_listing
there's a cap list here: http://www.juniorsrevenge.com/nanaoms929caplist.txt

I'm sure there are other lists floating around online too.

If this were mine I'd make a spreadsheet, in the first column put the cap location number, in the second column put the farad and voltage as specified on your cap kit list, then in columns 2,3, etc list out the caps specified in any of the online lists you've found. Finally look at each cap you installed on your board and mark the farad and voltage in it's own column also check the polarity of the cap against the polarity on the silkscreen (note that the silkscreen marks the positive pin while the cap casing marks the negative pin) ...

Do you still have the old caps? if so try to figure out which cap went to which location and mark down the value in it's own column on the spreadsheet

highlight any row where any differences exist... ESPECIALLY if the farad rating is different or if your new cap has a lower voltage rating than any of the other columns.

I've not done done an MS9 cap kit but it seems as though the pi-polar cap can indeed keep it from running if a suitable replacement is not used: http://forum.arcadeotaku.com/viewtopic.php?t=19053

If your new cap is not by polar then re-install your old one in that spot. Same goes for any location where there is a mis-match (wrong farad rating to voltage to low).

I would do all this first and check over all the boards for cold joints or damaged traces, re-flow as needed. test before swapping back the HOT. if the above fails to revive the board then replace the HOT with the old one and be sure to reinstall the plastic isolation shield if it had one and use non-conductive thermal paste.

Also wheres the best place to buy caps?
Depending on your chassis you don't have much choice unless you build your own. I've bought from Ian Kellog, from Arcade Buffett, From Arcade Cup, from Twisted Quarter, Syracuse Semiconductors. They all use high quality caps and include decent documentation. The only place I wont order cap kits from again is Bob Roberts only because the few kits I've ordered from him used cheap low-quality caps.

As I said I've never had a kit that matched 100%. the best kits will only have a few caps with higher voltages than the originals, which should be fine, mistakes are made sometimes so if anything beyond that is off I'd rather skip that cap, document it and move on. Replacing it with the wrong value cap can cause more problems. In most cases there are only a handful of caps in high-stress areas that are problematic but it would take more time to test each and every one (to properly test a cap it needs to be removed anyway) so it just makes more sense to replace them all. but if anything is out of the ordinary you're better off sticking with the original cap so long as it's not visibly bloated or leaking (in which case you should order a proper replacement if one was not included with your kit).

EDIT:
I should note most places that sell cap kits have never actually attempted to use their own cap kits. They buy capacitors in bulk and and then build the kits from cap lists online or from the chassis schematics. Which is fine, but that's a big part of the reason you can't 100% trust anything but the old caps that are already installed din your monitor.
 
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Posting some detailed pics of your chassis would be good to identifying the exact revision. IIRC there are at least 5 variants (maybe more) of the MS9-29 and it's possible that the cap list is different between them.

MS9-29A (Astro chassis variant with manual degauss)
MS9-29N (Namco maybe?)
MS9-29T (Taito chassis variant with auto degauss)
MS9-29S (I don't know where this one was used)
MS9-29SU (Sega Universal chassis variant, designed for Hitachi tube, found in Twin units and other Sega machines)
Thank you for taking the time to write this up I really appreciate it. I still have my old caps so i am going to write up and compare as you said. I will also takes some detailed pics of my chassis.

Thanks guys!
 
Just reading online and people have swapped the HOT, how would I know if its not working correctly? I still have the original.
There was nothing wrong with the original. You had a working picture, didn't you? A green tint could be caused by a bad pot, bad capacitor, bad diode, bad resistor, bad monitor, any number of things really, but not a blown HOT.
For bad color, I start with the pots and 9/10 it solves the issue. If a color is completely missing as indicated in test mode, then 9/10 it's one of the three RGB transistors on the neck board. Anything else is rare. No cap kit needed.
 
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For bad color, I start with the pots and 9/10 it solves the issue.
...
No cap kit needed.
While this is technically correct. if the colors have fallen out of adjustment it's usually an indication that the caps are weakening and on their way out. So while you can fix it by adjusting the pots it's been my experience that after a few months of regular use you'll be adjust them again, and eventually it will get far enough out of whack that the pots don't have the range to compensate for the failing caps and you'll have to do a kit anyway.
 
^ In that scenario, a new pot would have no effect. I'm saying if the replacement pot fixes the issue, then it was the pot and not the caps and you're done.
 
I thought you were suggesting adjusting the pots not replacing the pots... pots do go bad but it's usually pretty obvious when they do and different symptoms than bad caps bad pots will generally cause flickering in whatever setting they adjust. sometimes they're cracked in which case they need to be replaced but usually it's just corrosion which can be fixed with a little bit of contact cleaner and wiping the pot lock to lock a few times (while powered down) before readjusting.
 
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