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A68KSA30X and MS9

IPD

IPD

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I have a 29" Hitachi A68KSA30X monitor without chassis in storage, only the tube. It originally came from a Sega racing cab (and I believe it had a Sanwa chassis at the time). There's almost no burn, so I'm tempted to try and see if it works.

Is this compatible with a Nanao MS9 chassis? According to Google it may work, but it's probably better to ask here before I try anything. 8)

IMG_3493.jpg


IMG_3494.JPG
 
Looks like the Hitachi I had in my Virtua Fighter 3tb. That had a MS9.

As said before, measure the yoke to be sure, but it should be good to go.
 
Thanks. I didn't have anything to measure inductance with, so I ordered one of the tools recommended from the thread linked above.

I'll report back once I have the values from the yoke.
 
You can measure the resistance for a ballpark figure. Just be aware that if you're using a cheap multimeter to do this, the meter will likely have internal resistance that you have to subtract from your readings.
 
I did some yoke measurements today on the Hitachi A68KSA30X:

Horizontal: 0.5 ohm / 0.34 mH
Vertical: 7.7 ohm / 18.3 mH

I compared this with two MS9 yokes on two Toshiba A68KJU96X tubes and got (same on both):

Horizontal: 0.7 ohm / 0.35 mH
Vertical: 6.6 ohm / 15 mH

I used my Fluke 177 multimeter for resistance, and a cheap UNI-T UT603 for inductance.

So I guess this might be a good fit, right?

Only problem now is that the previous owner cut one of the yoke connectors on the Hitachi tube, so I need to source replacements somewhere. JST-LV and JST-V could work, but I don't see them in stock anywhere.
 
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The vertical connector:


IMG_3612.JPG
 
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Heater resistance in the chassis should be different when using a Hitachi tube and a Toshiba tube.

IIRC ms9-su chassis (tipically paired to Hitachi tube) has a 1.5 Ohm heater resistance. However any other ms9 chassis model paired to Toshiba tubes has a 3.3Ohm on it.

Not really a problem, but if you install, let's say, a ms9-A into a Hitachi tube, you would got a dimmed image
 
Finally found the correct connector for the vertical wires today. Grabbed one of my spare MS9-29 chassis, triple checked everything and .... it works. :)

Colors need adjusting etc, but I'd say this was a success.

IMG_3620.JPG
 
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This Hitachi kinescope was natively mounted with MS9 chassis, any MS9 chassis can be used and will work however on the MS9 29SU (hitachi tube) some changes were made to fit the chassis perfectly to the Hitachi tube, they are only two and very simple.

1) The R532 filament resistor must be 1.5 ohm for Hitachi tube while it must be 3.3 ohm for the Toshiba tube. As you can imagine with a 3.3 ohm resistor you will get a darker image on a Hitachi tube.
2) The S correction cap, which serves to modulate the scanning speed on the sides of the grid to obtain a perfect proportion of the squares of the grid on the sides with respect to the center is different because slightly different is the curvature of the hitachi tube compared to the toshiba so c531 will be a film cap 564j 200v on the hitachi set while for toshiba tube 334j 200v.
 
Mukuro_W said:
2) The S correction cap, which serves to modulate the scanning speed on the sides of the grid to obtain a perfect proportion of the squares of the grid on the sides with respect to the center is different because slightly different is the curvature of the hitachi tube compared to the toshiba so c531 will be a film cap 564j 200v on the hitachi set while for toshiba tube 334j 200v.
Click to expand...
If you plan to change the S-caps to fit the tube as @Mukuro_W stated above, you may also want to keep the total capacitance of the 2 S-Capacitors present in MS9 chassis, in order to prevent affecting the 15KHz mode working.

C519 and C531 have a total capacitance of 1.15uF. If you replace one of them, you also need to change the other one, maintaining that total capacitance, but in a different proportion between two of them..

For Toshiba tubes they should be: C519: 824J and C531: 334J

Source: http://mikejmoffitt.com/pages/ms9-hax/
 
No, it is no correct all the H. Stage film caps are the same value on both toshiba and hitachi chassis except c531 which is bigger on the ms9su (hitachi tube) due to archive a perfect proportion on the grid in normal mode (normal/wide selector) no matter if you are running 15 or 24khz. This was made by factory.
 
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How far off is the curvature of the Hitachi vs the Toshiba? I want to put these in a set of burned NACs I purchased recently and if the gap is small, I can deal with it with some closed cell foam. Hope it is a gap and not the bezel doesn't fit is all. If anyone knows, would be helpful.
 
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