Yoke and tube specs for monitors

[wwse]

My friend check his A68LTF356X - 3C revision.
29Y - found the same inscription in the tube with revision 0453
A II5
III

In one of the CRT TV with A68LTF356X I found, some of the inscriptions cover the speaker, but I clearly see II (the part under the speakers) and 0 at the bottom - very similar to your photo.

 

[thegreathopper]

Does anyone know if a matsushita M68JUA068X is a direct replacement for a Toshiba A68KJU96X, they both come connected to a Nanao MS9 chassis. I wanted to connect the Matsushita crt to a Toshiba PB-6643 chassis.

I think these are all interchangeable but Hoping someone knows for sure.

Thanks.

 

[yosai]

Steve, I've got an MS9 chassis if you want to trade.

 

[Nebula]

Does anyone know if a matsushita M68JUA068X is a direct replacement for a Toshiba A68KJU96X, they both come connected to a Nanao MS9 chassis. I wanted to connect the Matsushita crt to a Toshiba PB-6643 chassis.

I think these are all interchangeable but Hoping someone knows for sure.

Thanks.

As far as I know, each one uses a different heater resistance, so apart from yoke specifications, also take care of that.

 

[thegreathopper]

Steve, I've got an MS9 chassis if you want to trade.

Lee, It’s to soon to do that I think, I do have a MS9 chassis that came with the Matsushita but it’s currently dead. But I want to see how the Matsushita looks it may be no good but looks to be burn free.

I suppose I could have a go at fixing the MS9 or send off for repair, I wonder who is best to do that, I think Grant is currently not doing repairs.

 

[thegreathopper]

As far as I know, each one uses a different heater resistance, so apart from yoke specifications, also take care of that.

That’s what I thought, I can measure the Yoke inductance - looks to be missing from this thread so could to get recorded. But heater voltages I understand are hard to measure…

 

[Nebula]

That’s what I thought, I can measure the Yoke inductance - looks to be missing from this thread so could to get recorded. But heater voltages I understand are hard to measure…

I was checking my old notes and I saw that the heater voltage is different between tubes A68KSA30X and A68KJU96X and therefore there is a different heater resistance in the chassis paired to each tube.
Really don't know about the Matsushita one, but you could check the value of R532 in your dead ms9 chassis to figure out its value.

 

[thegreathopper]

R532 is Brn-Grn-Brn-Brn, Which I make 150 Ohms, does that sound correct?

After a 2nd look it is Brn-Grn-Gold-Gold = 1.5 Ohms.

 

[Nebula]

R532 is Brn-Grn-Brn-Brn, Which I make 150 Ohms, does that sound correct?

Comparting that with the values of that resistor in the MS9 paired with Toshiba tube, and the one paired with Hitachi tube, that doesn't make much sense...

I presume it should be: Brn-Grn-Gold-Gold, that is 1.5 Ohms, and that matches with the resistor in MS9 paired with Hitachi tube (KSA), so Matsushita tube is the same as Hitachi in terms of Heater voltage.

For the Toshiba one (KJU), the resistor is: Orange-Orange-Gold-Gold, that is 3.3 Ohms.

Anyway, if you don't change this resistor, this is not harmful. You probably get a dimmer picture only.

 

[thegreathopper]

Comparting that with the values of that resistor in the MS9 paired with Toshiba tube, and the one paired with Hitachi tube, that doesn't make much sense...

I presume it should be: Brn-Grn-Gold-Gold, that is 1.5 Ohms, and that matches with the resistor in MS9 paired with Hitachi tube (KSA), so Matsushita tube is the same as Hitachi in terms of Heater voltage.

For the Toshiba one (KJU), the resistor is: Orange-Orange-Gold-Gold, that is 3.3 Ohms.

Anyway, if you don't change this resistor, this is not harmful. You probably get a dimmer picture only.

I think you are right, Gold and Brown look similar on a dusty chassis, I will post a pic later, Also have an inductance meter coming tomorrow will post the Yoke impedances.

Thanks

 

[thegreathopper]

Here is my resistor pic and L &R readings.

 

[thegreathopper]

My Inductance meter arrived and I am reading on the 2 yoke coils.

Looks pretty close to the Toshiba tube, so looks like I just need to change the heater resistor value on my Toshiba chassis..?

Any idea which one?

Matsushita M68JUA068X
6.9 Ohms
0.26 Ohms

12.8 mH
0.32 mH

 

[Nebula]

My Inductance meter arrived and I am reading on the 2 yoke coils.

Looks pretty close to the Toshiba tube, so looks like I just need to change the heater resistor value on my Toshiba chassis..?

Any idea which one?

6.9 Ohms

0.26 Ohms



12.8 mH

0.32 mH

You can use a 3.3 Ohms 1W for that. But only if you plan to use the MS9 chassis. I don’t really know about Toshiba PB chassis

 

[thegreathopper]

Thanks, what I want to do is try the Toshiba PB chassis with the Matsushita tube.

 

[chriszhxi]

Has anyone in the US been able to successfully tube swap and MS9 from a consumer TV donor? Where screen curve is an exact match and depth of the tube does not produce convergence/purity/focus issues?

My experience with the MS9 is finding a suitable donor tube from a consumer TV is impossible. I've found tubes that match the screen curve. But of all those that have matching screen curve, the dimensions in the back of the tube are too deep to fit into an MS9 frame with the chassis installed. You'd have to modify the chassis tray so it sits further back on the frame to have enough clearance for the tube to be mounted without it touching the chassis.

Once you solve the physical challenges, of course you have to do a yoke swap. I have yet to find a yoke from a 29" TV that is compatible outright. The yoke swap isn't a big deal. But now once that is solved, then you have the challenge of the MS9's beam being very short (distance from the gun to the screen). All the consumer TV's I have tried will have purity and convergence issues that are impossible to solve.

I have only found a suitable MS9 donor from a lesser brand arcade monitor. My opinion is if you use a consumer TV as your MS9 donor, you are looking at a tube that is is flatter. More suited for an MS293x. You'll then have to mask the gaps between the screen and bezel. I've went through like 40 donors and zilch are suitable for the MS9. That has been my experience in the US anyway.

Yup, I recently got a tube from a Toshiba TV, the tube model is A68LJM256X, it's a little bit flatter than MS9. And it actually is more "deeper"than MS9, not "fatter", which means it sits at more back position once installed on the frame, leaves a big gap between tube and bezel, and also not enough space for chassis at the back.

I swapped the yoke, the result turned out to be weird. It has "huge" scanlines which is not usable.

Do you have any experience for consumer TV for New Net City? Since it's flat, it may have more choices. Right now I'm looking at some Toshiba consumer TV, but afraid ended like the one on MS9.

 

[RealMFnG]

Yup, I recently got a tube from a Toshiba TV, the tube model is A68LJM256X, it's a little bit flatter than MS9. And it actually is more "deeper"than MS9, not "fatter", which means it sits at more back position once installed on the frame, leaves a big gap between tube and bezel, and also not enough space for chassis at the back.

I swapped the yoke, the result turned out to be weird. It has "huge" scanlines which is not usable.

AFAIK, the only source for suitable MS9 tube swaps are from other arcade monitors. I haven't found a suitable donor for an MS9 from a consumer TV. And I have done lots and lots of searching.

That tube you have might work for a Blast City however.

Do you have any experience for consumer TV for New Net City? Since it's flat, it may have more choices. Right now I'm looking at some Toshiba consumer TV, but afraid ended like the one on MS9.

Nope. My NNC tubes are beautiful. Plus I have two spares from racing cabs .

I know you can find the tubes from Wangnam racing cabs. Wagnam 1 comes with Sanwa 2931ES monitors. Wangnam 2 comes with Sanwa PFX tubes with Novell tubes.

But yeah, there should be more 27" flat panel 4x3 TV's out there. But no idea what your chances of success are going to be. @Hedonism Bot 2.0 has put some effort into the same endeavor for the NNC without luck.

 

[Mukuro_W]

My Inductance meter arrived and I am reading on the 2 yoke coils.

Looks pretty close to the Toshiba tube, so looks like I just need to change the heater resistor value on my Toshiba chassis..?

Any idea which one?

Matsushita M68JUA068X
6.9 Ohms
0.26 Ohms

12.8 mH
0.32 mH

This was paired with latest ms9 revision, D1.. There are also some mods on this chassis including a film cap across the H driver transformer pins in the h stage. This tube will work with any ms9 chassis but you eventually can get some minor geometry issue.

 

[thegreathopper]

This was paired with latest ms9 revision, D1.. There are also some mods on this chassis including a film cap across the driver transformer pins in the h stage. This tube will work with any ms9 chassis but you eventually can get some minor geometry issue.

Thanks, yes I just checked this chassis and it is is a D1 revision. I thought it was dead but after recapping and replacing the fuse on the Nanao MS9 chassis it works!

The Matsushita M68JUA068X gives a great picture, as good as a Toshiba? not quite but it’s very good.

 

[chriszhxi]

But yeah, there should be more 27" flat panel 4x3 TV's out there. But no idea what your chances of success are going to be. @Hedonism Bot 2.0 has put some effort into the same endeavor for the NNC without luck.

I just found a Samsung A68QFN899X002 tube with Sanwa chassis, seems pretty new and unused, seller says it's old stock. But the Sanwa chassis may be a replica because I don't see sanwa label on it only says KW0606A. Is the tube compatible with Toshiba PD9929 chassis?

 

[RealMFnG]

I just found a Samsung A68QFN899X002 tube with Sanwa chassis, seems pretty new and unused, seller says it's old stock. But the Sanwa chassis may be a replica because I don't see sanwa label on it only says KW0606A. Is the tube compatible with Toshiba PD9929 chassis?

KW0606A is a Sanwa PFX. No idea if the tube is compatible with a Toshiba PD9929. What I do know is that in an NCC, you can find either a Sanwa PFX or a Toshiba Pure Flat. You'll have to put in the work and find out. Let us all know what you find out.

Don't forget to use grease pens or something to mark the position of the yoke in case you have to put things back together. Because to make it work, you'll have to do a yoke swap.