MS9 Recap question

Gents, I'm finally getting around to my first MS-9 29T monitor recap. I had an old Arcade Parts and Repair MS9-29 cap kit around so that's what I'm using, but came across three questions.

C403 is a ceramic cap on my chassis. Is this an error?
C955 is 180µ 25v. Is this an error?
C987 is... not on my chassis. Is this an error?


And to heck with it, here's a fourth bonus question. I'm going to do the sharpness mod after this recap to ensure my recap was done correctly. Should I bother to adjust the B+ after the recap, or just do a quick test to make sure the chassis works, pull it off, sharpness mod it, then adjust the B+?

Looks like you got a MS9-29A cap kit which is the standard.
I don’t think APAR has a specific T variant of their cap kits.

The differences in caps between the variants are usually one or few caps having different specs. My advice is to replace those ones that are not in the cap kits with what they are on the chassis. You’ll probably have to order those separately.

As for the B+ for the Nanao MS9’s you can adjust before or after.
The flybacks on the MS9’s run fairly cool overall, so you can push the b+ up a bit and it doesn’t need to be exactly set to 76v for 15khz. It could be “around 76v” and still be fine.
I like to push my b+ voltage to about 77.5v for some extra brightness. The flyback can handle it.

Also more on this topic:
You might have the MS9-29S or SU variation.

It’s perfectly fine to use the supplied 220uF 50V cap from the kit for C955. I’ve done this on several S rev chassis’s and it doesn’t pose an issue.

Leave C403 alone and don’t worry about replacing it (unless it’s actually failed).

Also ok to ignore C987 from the kit since the S rev chassis do not have that cap.

At the end of the day, the APAR MS9 standard cap kit is the right one for your chassis. It’s just the slight variations of the board revs has a few different caps. But you are totally fine with that kit.

I have just finished 2/3 chassis recaps. This one is a SU, and I used the APAR standard kit for it.
It got a new color amp, HOT, and sync IC’s too. Probably my nicest chassis right now. Lol

Thanks for the info bro. I'm on a slight pause, about halfway done, but I'll finish up, post some pics and before/afters on the sharpness mod. I also see no one ever did pics for it, so I might as well take some along the way for that thread.

Yours looks awesome, those colors are popping.

By the way, I don't use a step down transformer, never have with candies, but I've heard it pushed the monitors sort of hard since they are expecting 100 vice 120. What do you do and have you noticed they run hotter if you don't do a step down?

Here in Europe we have to step dow from 2x0 to 100 for obvious reasons. I would definitely be on spec whenever possible, even having some tolerances.

XtraSmiley said:

By the way, I don't use a step down transformer, never have with candies, but I've heard it pushed the monitors sort of hard since they are expecting 100 vice 120. What do you do and have you noticed they run hotter if you don't do a step down?

Click to expand...

I’m the same, I don’t run stepdown converters with my cabs. None of the local places I help service cabs for do either. Barcode for example has 10 candy cabs, Don’s Arcade has 14 and none of them run stepdowns, and they run their cabs for many hours on end.

I think it’s totally fine for this chassis/monitor since the Nanao’s run fairly cooler than most arcade monitors. But here in North America you don’t really need to worry about it unless you are ocd about it.

You don't need a step down from 120v to 100v. Adjust the B+ to the correct value and it'll be fine.