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tengugurl

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Hi my fellow enthusiasts! ❤️

I am working on a tube swap in my Blast City that has a stock Nanao MS-2931 that needs replacing.

I got a backup monitor to replace it.

Info:
1) Tube pitch/angle is same

2) Montiors measure the same size even though the Nanao is supposed to be a 27"??

3) Measured the Ohms resistance on the Horizontal and Vertical ports on each CRT they read as below:

Nanao MS-2931
Horizontal (Red/Blue) 3.4 ohm
Vertical (Brown/Grey) 7.0 ohm

Craigslist TV
Horizontal (Red/Blue) 1.5 ohm
Vertical (Yellow/Green) 5.7ohmI

4) Pins
Both are 9 pin (same pattern) and have a matching yoke lengths as well

Question:
**Will this monitor work if I wanted to keep the craigslist Yoke on, or is this too far out of the 10% variance that I will need to use the stock Nanao Yoke and put it on the donor tube?**

Side question, if a CRT doesn't have the typical horizontal/vertical color pattern of Red, Blue, Yellow, Green but, instead has Red,Blue, Brown, Gray

*Does green =brown
Or does Gray = brown?

Thanks for any help you can provide!
Cant wait to learn how to do this and your help would be greatly appreciated
 

tengugurl

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Oh nice! Okay, I am going to pick one of those up

So I am a dumby... The board is not a 2931, it's an MS9-29 PCB. I have to buy the right cap kit now lol!

My cab is a Frankenstein cab and has lots of stickers/parts that refer to another model.

So once I get my BSIDE ESR20 Pro, test the inductance and get the ratings the same way I saw on YouTube via Horizontal (red/blue) ports and the vertical ports (brown/gray) on the Nanao, then do the craigslist tv?

Do you know which color Brown/Gray corresponds to Green or Yellow?
I was told it won't hurt anything to install the vertical colors incorrectly as it will just flip my image upside down until I match the brown(?) To the green or gray(?) To Green/yellow etc ..
Just don't cross the streams jk. (don't cross vertical or horizontal and you will be golden, right?
 

RealMFnG

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You can also send in your MS2931 to PNL Video or Sharper Image for repair and save some trouble.

Screen curve on the Blast City tube and the MS9 are different aren't they, so fitment may be an issue once you get to that bridge.

Here is a neumatic tip for installing Nanao yoke connectors in the correct orientation that I have taught myself: B = Left. Which means, if looking at the chassis from behind, flyback nearest to you, the color wire that starts with a "B" should be on the left position. So you have:
  • Blue/Red - The Blue wire should be on the left position on the horizontal connnection
    • The horizonal connection is closest to the flyback and has wider spacing than the vertical circuit
  • Brown/Gray (or White) - The Brown wire should be on the left position in the vertical circuit
 

nem

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I was told it won't hurt anything to install the vertical colors incorrectly as it will just flip my image upside down until I match the brown(?) To the green or gray(?) To Green/yellow etc ..
Just don't cross the streams jk. (don't cross vertical or horizontal and you will be golden, right?
That's correct.

Just wire up horizontal to horizontal, vertical to vertical. You can flip the yoke connectors if you have either (or both) reversed.

If you mix the yoke connectors, you can blow the chassis.
 

tengugurl

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You rock! Thanks :)
Good to know I won't blow my chassis/tube if I ensure not to mix them.


Can't wait to come back with those readings.
Urghh hurry up Amazon lol! There is a pandemic going on so I'll need to practice more patience.
 

tengugurl

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Hi!

Okay, so I ordered the ESR02 but it's coming from China.... So I installed the monitor anyway haha!

I saw a video on YouTube that said "if the pins match up and it's basically the same shape/ size, it will work.'

I took the bonded yoke off the craigslist tv (that was a pain!)
Installed my PCB with all new caps and tada! I had a picture the first go round! ❤️

Prob is that the convergence is way off!
I spent the whole weekend playing with magnets, moving the yoke back and forth, moving the rings round n round until I got it this far *see link to IMGUR
http://imgur.com/gallery/syLg2EB

It's far from perfect and there is bleed that I just can't seem to get rid of, any pointers?

Also, the picture wants to be round, it's like it won't flatten out. I went into the factory settings (hit all 3 buttons menu, up, and down) on that nanao and played around with it until I learned green means to close, red is perfect, purple is almost there and blue means you wayyyyyy off. @240p suite.

I dream of that freaking horizontal test pattern now... No joke it will be the end of me!

I would love any pointers, and or any help from someone who has done a tubeswap successfully as mine went from:

Looking like a used and abused mall arcade with Burn in near the 99cent store to broken down machine that's going to be retired to sit in front of the 99 cents store. Not what I expected a weekends work of caps, playing with magnets and research would provide lol
 

nem

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"if the pins match up and it's basically the same shape/ size, it will work.'
This isn't true. Not all tubes will work with all yokes.

So what have you actually done? Did you drop the original Nanao yoke on the new tube? Did the original tube have a yoke ring set? Which ring set are you using?

You should reset the chassis back to factory settings. You have to get it looking OK with those, any adjustments on the chassis are for fine tuning.
 

tengugurl

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Dang @ not all tubes will work... :(

I dropped the Nanao Yoke into the new tube as the donor tube had a bonded yoke with no adjustment rings. Removing the bonded hard glue crap was a pain as I didn't want to damage the tube.

The adjustment rings I am using are from the Nanao tube.

Okay, there is a reset option luckily in the factory mode.

I got another tube yesterday just Incase but it has the same bonded yoke like the current donor tube has with no adjustment rings.
 

nem

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I think those tubes that don't have a separate adjustable ring set can have problems with a different yoke. That's been my experience lately.
 

Metal Slug

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I just did a tube swap over the weekend on an Nanao MS9, and then I came across this thread so I figured I would share my limited experience while it is still fresh in my memory. My MS9 tubes are all Hitachi brand on the sticker, so I figured I would roll the dice with a Hitachi brand 27inch consumer CRT, I had luckily found one for free a couple months ago. I measured the yokes and both were within 0.2 of each other and they look almost identical. So, I just hooked the MS9 chassis up to the Consumer Hitachi tube without swapping yokes first to see what it does, and surprisingly I got an "OK" picture! The convergence was a bit off, but more importantly the width adjustment seemed to make no effect to the image. I couldn't fill the screen with the image width wise. Next, I swapped yokes and everything worked!

Some tips that seemed to make a difference for me, first make sure the yoke is as far up the neck as it can go, it can get caught and friction can hold it just slightly back and will cause an awful image. Second, my MS9 yoke actually had a couple purity magnets taped inside the yoke that I left on originally, they caused a couple discolorations that went away when I removed them. Lastly, (and less of an option for you since your tube had no adjustment rings) I swapped between the adjustment rings from the old tube to the new tube to see which gave me better control, and the original MS9 adjustment rings seemed to work best for me.

I did discover that the new tube is actually deeper then the original once I de-cased it from the Hitachi shell, the neck board protrudes just slightly behind the MS9 frame. This may be a deal breaker when installing it in some cabs due to clearances. I had always read that the tubes had to be the exact same in dimensions for it to work. So its all a bit of a crap shoot I guess?

Convergence adjustments and magnets are truly awful to work with, they'll make your eyes cross and you'll feel very frustrated at times. I felt super stupid when I used a deguass ring to try to tweak some color spots popping it on just off to the side of the monitor to try to clean up a discoloration... then I started adding purity magnets. Once I got it pretty good with geometry straight and colors clean, I placed it near another monitor to compare... I degaussed the other monitor and it threw all my work right out the window! Make sure you are working on a cleanly degaused tube before adding purity magnets... LOL!
 

tengugurl

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Wow! Congrats on the successful swap!
So keep an eye out for a Hitachi 27" hehe
Cool

The tube came from a Samsung TV, it's a 27V1R 1.3 http://imgur.com/gallery/nnPR7cxv

Pics of my convergence work and adjustment rings from the nanao on the Samsung donor tv
 
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