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Can a MS2930 work with an A68KJU96X?

net_terminal_gene

net_terminal_gene

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Hi there. I have a Blast City cabinet that came with a reverse mounted Toshiba A68KJU96X tube with a non working MS2930 that automatically goes into protection mode. The chassis was sent back to seller which was then sent to PNL.

I recently ran across this AO WiKi , where it makes it seem like out of all the MS29XX series, the A68KJU96X is only compatible with MS2932. Is this true?

Known tubes:
Toshiba A68KJU96X / MS2932 : H :0.4 Ohms V:7 Ohms
Toshiba A68LBT696X / MS2931 : H :0.9 Ohms V :6.8 Ohms
Toshiba A68KZN696X / MS2930 : H :0.5 Ohms V:6.7 Ohms
Click to expand...

I’d rather find a chassis than tube if that’s the case. I’m looking for some insight on determining my next steps.

a. Continue trying to fix the MS2930 because it will work.
b. Find a MS9-29 + Yoke

I’m totally fine with 15khz running through this cabinet if MS9 is my only option. I have an AC and NAC both with MS9-29 + A68KJU96X that I plan on doing the Moffitt 31khz upgrade.

Any help would be much appreciated. Thanks.
 
A68KJU96X will not fit into a blast city due to a different curvature of the tube itself, A68KJU96X can be paired with ms8 29, ms9 29, Toshiba pb6643, ms2932 (31khz/VGA only) BUT you need also the correct yoke since only ms9 and pb6643 are interchangeable on the same yoke!
You can still mount an ms8 29:chassis on a A68KJU96X +MS9 yoke but your geo will never be ok, ms2932 need its yoke otherwise it will not suitable.
 
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Had the 2930 previously been working with this tube? I only ask because the 2930 chassis is not typically compatible with the ms9 tube. If it was working I would assume the JU96X tube has a 2932 yoke already placed on it maybe?? You need to know what yoke you actually have.

The way I see it you have 3 options.
  1. find an ms9 chassis these chassis are very reliable would be my first option provided that i had a ms9 yoke or could get one.
  2. find and fit a toshiba pure flat tri sync or D2955 (15k only) I think davesarcades has one for like 400.00. Again provided the yoke is for an ms9 not a 2932
  3. If the yoke is not an ms9 yoke you have to go with a ms-2930-ms-2934 chassis. The 2932 & 2934 are 31k only. I have a 31k ms2934 chassis that might work I could sell you for 250.00
 
All Nanao trifreq monitior sets have lots of issues, the chassis can destroy the tube itself, the flyback can fail, the yoke was assembled with poor parts (all develope convergence issues overtime, inner magnets auto destroy due to the heat)....
Pure flat tube will not fit on the Blast.
I think that you have two options:
1) 15/24Khz , replace the monitor with an ms9-29SU , this is an ms9 chassis paired with an Hitachi tube , very easy to find one also in no burn condition, it will fit pretty well on Blast bezel, just about 2mm of gap that you can fix with foam...
2) 31Khz only, use an ms2934 chassis, it is direct swap on 2930-31 tube, or find an ms2934 monitor set, it will obviously fit perfectly on the Blast, the only downside is that it is a 31khz only chassis.
 
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@Mukuro_W @garou81

Thank you so much for all this valuable info. I really appreciate the help. Sounds like no matter what the chassis + tube combo is a non match even if the MS2930 were to be fixed.

@Mukuro_W
All Nanao trifreq monitior sets have lots of issues, the chassis can destroy the tube itself, the flyback can fail, the yoke was assembled with poor parts (all develope convergence issues overtime, inner magnets auto destroy due to the heat)....
Click to expand...
This quote really resonates with me right now because there is more to my Blast City saga.

I actually own 2 non working Blast City cabinets I bought from KC Arcades in early December. I've purchased 3 other cabinets from him in the past with no issues (Vewlix, New Net City & New Astro City) hence why I took the gamble again. Before shipping what he will do is share a video of the cabinet "on and working" while finally walking around to the back to share the serial number to ensure you're getting the same cabinet.

@garou81
Had the 2930 previously been working with this tube?
Click to expand...
According to the video sent by KC yes, but not when it showed up to my home. Unless he takes video of a cabinet "working" then swap the chassis I'm beyond how this was working in the first place.

Here's the state of both cabinets when they showed up to my home.
Cabinet 1: Toshiba A68LBT696X + MS2931
  • Worked for a few minutes with my PolyGame Master system. Brightness was very low so I adjusted settings on the Remote Board and FOCUS / BRIGHT on the flyback. I then turned the cabinet off. When I turned it back on, that was when I unfortunately joined the "MS2931 destroyed my tube" club. There was sparking shooting through the tube neck and also a small spark shooting from the Yoke. Also, from then on the chassis would go into Protection Mode right away. I can hear a click on start up and the chirp after about a 45 seconds of the cabinet being shut off. I have been unable to locate a crack on the tube neck and hoping it could be salvaged but worse comes to worse I know of someone in my area that's willing to sell an extra A68LBT696X if the MS2931 can be fixed. Still hesitant of the chassis issues in general destroying another tube.
Cabinet 2: Toshiba A68KJU96X + MS2930
  • Monitor is reverse mounted and the bezel does not fit completely flush to the tube. It will latch but is bending pretty hard with gaps(I've read about the foam gap seal trick). This one never started with any system. Made sure the remote board was set to 15khz and no wires were loose. It would automatically go into Protection Mode. The tube would make that initial static sound but then the chassis protection click with chirp after cabinet shut off happens. Now sounds like the icing on the cake is that this chassis is not even the correct pair with the tube to begin with.
After all that I immediately reached out to KC and he said he would repair everything free of charge if I sent him the chassis back. For Cabinet 1, I sent him both the MS2931 and the YOKE because it was sparking. For Cabinet 2, I sent only the chassis. He then sent them to PNL. They are both still in repair as of late December.

All that said, it sounds like you two are recommending the MS9-29 route as first option. I'm out of town for the next couple weeks but when I get back I'll check to see what YOKE is actually paired with my A68KJU96X first.

@garou81
I have a 31k ms2934 chassis that might work I could sell you for 250.00
Click to expand...
I'll make this as a backup plan but would rather go 15khz first because I plan on running a PC build that only outputs that frequency.

@Mukuro_W
15/24Khz , replace the monitor with an ms9-29SU , this is an ms9 chassis paired with an Hitachi tube , very easy to find one also in no burn condition, it will fit pretty well on Blast bezel, just about 2mm of gap that you can fix with foam...
Click to expand...
If I can't easily find one, are there any dedicated cabinets that I may find a HITACHI A68KSA30X in? Like how Daytona USA and Virtual On usually has Toshiba A68KJU96X. Hoping maybe a as is parts cabinet is close by.

Again, thank you two so much for the help. I'm determined to get these cabinets finally working.
 
Ms2930/31/33 will all work interchangeably.

The 2930 and 31 use the same flybacks the 33 uses a totally different flyback and HV control daughter board.

The biggest issue with the 2930 / 2931 is pretty much the flyback. Shorting flyback is a absolute catastrophic event you can only do so much to prevent it from damaging the board or tube.
That is why there is a High Voltage control IC and shut down protections.

But even so they could only design so much and if the flyback shorts quickly enough, the HV ramps up to fast and goes out of control faster than the HV Shutdown can react it will internally arc to the electron gun assembly to ground its self.

This will ofc kill the gun assembly and seems to crack the neck of the tube. However its not an ultra common thing but when the flyback is shorting its like rolling a dice because its such a catastrophic type of failure.

The 2930/31 runs great until it has any serious failure modes then it becomes a nightmare to service.

Theres a replacement flyback option now available but its not OEM.
The original replacements were trash there's a newer model out now that has better build qualities should come out of spain. Sharp image gets them I have gotten some in the past on my boards from them.

While the flybacks do tend to go out on these, they are also really sensitive to shutting down and the circuits are complex. You really would want a professional to work on it.

As for putting different tubes into a blast. Yes you can put a MS9 monitor into a blast. No the curvature does not perfectly fit however it fits enough as @Mukuro_W says it will leave some gap.
The plug for the main RGB/AC for the MS9 and MS293X are also pin compatible. You could try to mod the MS9 to do 31khz and then you have a chassis that does 15khz and 31khz but thats outside the scope.

In terms of chassis compatibility your really looking at the yoke impedance and the tube size (for the HV). All these 29inch tubes from this era should be using the same pin outs heater and g1 voltages it was kinda standardized by this point unless its multi focus or some weirdo thing or sony.

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

Personally I would just put a full MS9 in the thing until you can rebuild a proper replacement MS293X monitor.
 
Of course they are from KC, what is he saying about the status of the repair It shouldnt take 3 months to repair a chassis.

I suspect that 2931 tube is done, grab that spare tube asap.

If it were me (and it was when I bought 2 blast cities sight unseen from KC) I'd ask for a partial refund and find my own solutions. Hunt around locally for any Sega Cabinet from the late 90's to 2000. I cant say for sure where youll find the hitachi tubes I think I might have seen one in a Sega superGT.

Suitable Blast City Replacements
  • Wells Gardner D9400 ( kinda loud but fit pretty well I've heard, I have no first hand knowledge of this)
  • Sanwa pfx and toshiba pure flat These might be found in konami and namco cabinets(Time crisis, wangan max tune, mario kart etc..). I dot know if its the age but these imho produce a far superior picture to the nanao. I got rid of mine becasue I couldn't deal with the bezel gap. They have to be reverse mounted with a couple washers.
  • Sanwa 29E31s found in early 2000's sega cabs like initial D stage 3 and king of route66. The fitment of these is perfect and they are compatible with ms9's but 75% of the ones I come across are missing a color.
Good luck
 
@GeekMan1222

Thank you for your insight and thorough details about the flyback issues.

Theres a replacement flyback option now available but its not OEM.
The original replacements were trash there's a newer model out now that has better build qualities should come out of spain. Sharp image gets them I have gotten some in the past on my boards from them.
Click to expand...
I remember when I started digging into my arcing issues I found the thread related to a finding an after market flyback and someone in Spain pretty much owning the bulk and selling. I also heard from someone recently that Sharp Image won't take any more MS29XX type chassis for repair. Since mine is currently at PNL, I'm thinking they'll most likely be replacing the flyback with that same model from the Spain seller.

Personally I would just put a full MS9 in the thing until you can rebuild a proper replacement MS293X monitor.
Click to expand...
I'm hoping at least with my A68KJU96X cabinet the yoke is an MS9 and all I'll need is the chassis. As for the A68LBT696X which I think is toast, let the tube, chassis and yoke search begin. I'm just really scared that if the MS2931 does get fixed, it's like putting a ticking time bomb back into the cabinet.

All great info. Thank you so much again.
 
@garou81

Of course they are from KC, what is he saying about the status of the repair It shouldnt take 3 months to repair a chassis.
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I sent the chassis off a right before the holidays started. I was told he sent PNL a total of 7 chassis including mine and that holidays may take a little longer. I reached out again a few weeks ago and he told me PNL lost his best guy and quit. I'm going to hit up PNL direct tomorrow and get to the bottom of this.

I agree that I should get compensated back some sort of refund. Especially for the cabinet that has faulty chassis and tube pair.

Suitable Blast City Replacements...
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Thanks for the insight on which cabinets may have the tube I'm looking for. Is the toshiba pure flat you mention the same as one found in New Net City paired with Tosh PF D29C051 chassis? I have one handy that I could see how bad the bezel gap is. I'm assuming if not mentioned already in the list, they are not compatible with MS9?
 
In my experience KC isn't taking any losses to make things right for a customer. The tosh pure flat is the same one found in the New net. I have seen the tosh pure flat chassis attached to an ms9 tube it looked marvelous. I would assume the reverse is also true but you do need to make up different yoke connectors if your interested I'll get the part numbers.

Here are my old pfx's in my blast. they really looked amazing. Ill ask the guy I got them from if he has more. He's in florida.
 

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garou81 said:
In my experience KC isn't taking any losses to make things right for a customer. The tosh pure flat is the same one found in the New net. I have seen the tosh pure flat chassis attached to an ms9 tube it looked marvelous. I would assume the reverse is also true but you do need to make up different yoke connectors if your interested I'll get the part numbers.

Here are my old pfx's in my blast. they really looked amazing. Ill ask the guy I got them from if he has more. He's in florida.
Click to expand...
Awesome. I love how my Toshiba PF D29C051 looks on my NNC!

Just to make sure I'm on the same page.

A68KJU96X tube:
It could possibly be paired with the Toshiba PF chassis. If this is true, this one up for sale right now. I would still need to figure out the Yoke if it's not an MS9 already. Will the AMP UP to the other pin connectors work as well like the RBG/AC, degauss? The one I have is most likely for MS2930 but according to @GeekMan1222
The plug for the main RGB/AC for the MS9 and MS293X are also pin compatible.
Click to expand...
Not sure if the Toshiba PF D29C051 can also be added into the mix.

Blown A68LBT696X tube:
You may know someone in Florida who has an additional tube or would this be chassis only? Would need a Yoke as well.

Definitely keep me posted about what yoke and the part number for the connectors. Thank you.
 
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