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Yoke and tube specs for monitors

nem

nem

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Let's start one of these as there seems to be interest in one. Hopefully everyone will contribute so we'll get a comprehensive list at some point.

For measuring the yoke, the tool that I use is the BSIDE ESR02 PRO. It seems accurate enough.

BSIDE ESR02 PRO- cheap tool recommendation

It's a really nice for this job, because it shows both resistance and inductance at the same time and keeps the values on the screen fixed for 15 seconds, which is enough time to jot them down or to snap a pic.

You can pick one up for around 20 USD. Remember to get meter leads for it.

---

Some specs can already be found here:

https://wiki.arcadeotaku.com/w/Yoke_Specifications

However, I would like to see additional info added to these.

---

The list will follow this format:

Monitor name (usually on a sticker on the frame somewhere)
Tube brand and model (sticker on the tube)
CRT base / neck connector (see here)
Chassis model (found on the PCB somewhere)
Yoke specs:
LhLvRhRv
for horizontal inductance in mHfor vertical inductance in mHfor horizontal resistance in ohmfor vertical resistance in ohm


---


Hantarex Polo 25 25khz (from European Sega Rally upright)
Tube: A59EAK552X44
Neck: B10-277
Chassis: Hantarex Polo 25 25khz
Yoke:
LhLvRhRv
0.31 mH4.82 mH0.7 ohm3.6 ohm


Hitachi GMK-29 (from Jaleco Pony IV)
Tube:
Neck: B10-277
Chassis: GMK-29
Yoke:
LhLvRhRv
0.25 mH19.0 mH----


Hitachi GMK-29FS2 (from SNK Neo 29)
Tube: A68KSA30X
Neck: B10-277
Chassis: GML MAIN P.W.B (?)
Yoke:
LhLvRhRv
0.36 mH19.0 mH0.8 ohm7.9 ohm


Nanao MS8-29 (from Sega Astro City)
Tube: Toshiba A68KJU96X
Neck: B10-277
Chassis: MS8-29
Yoke:
LhLvRhRv
0.39 mH17.5 mH----


Nanao MS9-29 (from Sega New Astro City, Taito Egret II, + others)
Tube: Toshiba A68KJU96X
Neck: B10-277
Chassis: MS9-29
Yoke:
LhLvRhRv
0.33 mH14.0 mH----


Nanao MS-2930 (from Sega Blast City)
Tube: Toshiba A68KSM696X
Neck: B10-277
Chassis: MS-2930
Yoke:
LhLvRhRv
0.20 mH16.0 mH----


Nanao MS-2932 (from Sega Naomi Universal)
Tube: Toshiba A68K**696X
Neck: B10-277
Chassis: MS-2932
Yoke:
LhLvRhRv
0.20 mH16.3 mH----


Nanao MS-2933 (from Sega Blast City, Sega New Net City)
Tube: Toshiba A68KSM696X
Neck: B10-277
Chassis: 05B20196E1
Yoke:
LhLvRhRv
0.19 mH15.1 mH0.5 ohm6.8 ohm


Sanwa 29e31s (from Sega Naomi Universal)
Tube:
Neck: B10-277
Chassis: 29e31s
Yoke:
LhLvRhRv
0.31 mH11.8 mH----


Sanwa PFX (from Sega New Net City)
Tube: Beijing-Matsushita A68MAU085X90
Neck: B10-277
Chassis: SXD60910A
Yoke:
LhLvRhRv
0.28 mH10.1 mH0.8 ohm7.6 ohm


Sanwa PFX (from Sega New Net City)
Tube: Toshiba A68LTF356X
Neck: B10-277
Chassis: KW0606A
Yoke:
LhLvRhRv
0.28 mH7.47 mH0.7 ohm6.1 ohm


Toei TC-L292
Tube:
Neck: B10-277 (?)
Chassis: TC-L292
Yoke:
LhLvRhRv
0.98 mH20.0 mH----


Toshiba D29CR55
Tube: Toshiba A68KJU96X
Neck: B10-277
Chassis: D29CR55
Yoke:
LhLvRhRv
0.34 mH14.4 mH----


Toshiba PB7574-1 (from Konami Windy II)
Tube: Toshiba A68KZN696X
Neck: B10-277
Chassis: PB7574-1
Yoke:
LhLvRhRv
0.22 mH10.6 mH0.6 ohm5.9 ohm


Toshiba PF D29C051 (from Sega New Net City)
Tube: Beijing-Matsushita A68LZU185X
Neck: B10-277
Chassis: PD2367
Yoke:
LhLvRhRv
0.29 mH11.9 mH0.8 ohm8.2 ohm


Toshiba PF D29C051 (from Sega New Net City)
Tube: Toshiba A68LTF356X
Neck: B10-277
Chassis: PD1843
Yoke:
LhLvRhRv
0.30 mH14.8 mH0.9 ohm8.2 ohm


Toshiba PF D29C051 (from Sega New Net City)
Tube: Toshiba A68LTF356X
Neck: B10-277
Chassis: PB9929
Yoke:
LhLvRhRv
0.30 mH15.2 mH0.9 ohm8.3 ohm


Wells-Gardner K7000 25"
Tube: Label absent/unreadable
Neck: B10-277
Chassis: K7000
Yoke:
LhLvRhRv
1.48 mH22.0 mH----


Wells-Gardner D9200 29"
Tube:
Neck: B10-277
Chassis: D9200
Yoke:
LhLvRhRv
0.248 mH5.89 mH----



Wells-Gardner D9400 29"
Tube: LG Philips A68QCU770XV6L
Neck: B10-277
Chassis: PCBKT279410-04R
Yoke:
LhLvRhRv
0.29 mH7.82 mH0.6 ohm5.9 ohm
 
Last edited:
Great stuff nem, thanks for taking those measurements.
 
So I have three "100% working" Toshiba PF's (PD1843's) coming from yaton. Will test them on NNC's that already have Toshiba PF's when they get here to validate "100% working" status. Then will install them on my Sanwa PFX-based NNC's to confirm compatibility. If I would have known this sooner, would not have spent any effort trying to assemble Martin Jones's Sync Pulse generator.

Also have one of those meters on the way.
 
NANAO MS2933
Tube: Toshiba A68KSM696X
Neck: B10-277
Chassis: 05B20196E1
Yoke:
LhLvRhRv
.19 mh15.1 mh0.5 ohm6.8 ohm


Sanwa PFX
Tube: Toshiba A68LTF356X
Neck: B10-277
Chassis: KW0606A
Yoke:
LhLvRhRv
.28 mh7.47 mh0.7 ohm6.1 ohm
 
Last edited:
Good catch @nem. Trippy how my A68LTF356X tube widely differs from yours on the vertical spec. But like you said, horizonal is what needs to be correct. Will be swapping out the Sanwa PFX for the Toshiba PF's this week.
 
Toshia PB7574-1 (Konami Windy II)
Tube: Toshiba A68KZN696X
Neck: B10-277
Chassis: ????
Yoke:
LhLvRhRv
.22 mh10.6 mh0.6 ohm5.9 ohm
 
I took a bunch of measurements a while back. I did not bother with DC resistance, only impedance.

Nanao MS9 (Sega New Astro City, Taito Egret II, many others)

Tube: Toshiba A68KJU96X
Neck: B10-277
Chassis: MS9-29

Yoke:

LhLvRhRv
0.33 mH14.0mH----



I've measured another with 14.6mH on the vertical.

Nanao MS8-29

Tube: Toshiba A68KJU96X
Neck: B10-277
Chassis: MS8-29 what a piece of shit


Yoke:

LhLvRhRv
0.39 mH17.5mH----




Toshiba Perfect Flat (New Net City)

Tube: A68LTF356X
Neck: B10-277
Chassis: Toshiba PF

Yoke:

LhLvRhRv
0.30 mH11.0mH----




Toshiba D29CR55

Tube: Toshiba A68KJU96X
Neck: B10-277
Chassis: Toshiba D29CR55

Yoke:

LhLvRhRv
0.34 mH14.4mH----




Sanwa E31s

Tube:
Neck: B10-277
Chassis: Sanwa E31s

Yoke:

LhLvRhRv
0.31 mH11.8mH----




Nanao MS-2930

Tube: Toshiba A68KSM696X
Neck: B10-277
Chassis: Nanao MS-2930

Yoke:

LhLvRhRv
0.20 mH16.0mH----




Hitachi GMK 29 (Pony Mk IV)

Tube:
Neck: B10-277
Chassis: Hitachi GMK 29

Yoke:

LhLvRhRv
0.25 mH19.0mH----




Toei TC-L292

Tube:
Neck: B10-277?
Chassis: Toei TC-L292

Yoke:

LhLvRhRv
0.98 mH20.0mH----



Rodotron 666A

Tube:
Neck:
Chassis: Rodotron 666A

Yoke:

LhLvRhRv
0.30 mH8.2mH----




Unknown Korean Samsung Monitor (GuitarFreaks)

Tube: Some Samsung
Neck:
Chassis:

Yoke:

LhLvRhRv
0.87 mH18.2mH----



25" Wells-Gardner K7000

Tube: Label absent/unreadable
Neck: B10-277
Chassis: K7000

Yoke:

LhLvRhRv
1.48 mH22.0mH----



Sony KV-27V42 Television

Tube: Some Sony Trinitron
Neck:
Chassis: KV-27V42


Yoke:

LhLvRhRv
1.21 mH22.6mH----




Nanao MS-2932

Tube: Toshiba A68K**696X (Blast tube)
Neck: B10-277
Chassis: MS-2932


Yoke:


LhLvRhRv
0.20mH16.3mH----


Wells-Gardner D9200

Tube:
Neck: B10-277
Chassis: D9200


Yoke:

LhLvRhRv
0.248mH5.89mH----
 
Last edited:
Awesome, thanks. I'll update the thread.

By any chance do you own that Pony Mk IV? I have a GMK-29FS2 in my Neo 29. When I received it two of the caps on the chassis had been replaced and they're both bulging. I think whoever replaced them might have put caps of the wrong value in. Are you able to check them for me?

Hatsune Mike said:
what a piece of shit
Click to expand...
Pffft
 
It's a friend's cab. The chassis just ticks and didn't boot, so it was taken out. I will ask if he still has it.
 
Hatsune Mike said:
It's a friend's cab. The chassis just ticks and didn't boot, so it was taken out. I will ask if he still has it.
Click to expand...
Let me know. The two caps are near the +B pot. C902 was 2.2uf 250V and the one to the right of it (C903?) 4.7uf 250V.
 

Attachments

  • gmk-29_caps.jpg
    gmk-29_caps.jpg
    113.4 KB · Views: 394
Monitor: Sanwa 27Z21c-A74A
Tube: YS BBQ 73SX707Y22-DC22
Chassis: 27Z21C-A74

Lh: 0.42mH
Lv: 17.71mH
Rh: 0.9 ohms
Rv: 7.6 ohms
 
I am looking at picking up a New Net City cab with some slight burn-in. The chassis is unknown because I don't yet have it in my possession, but I see that the following four tubes are used across all the NNC cabs listed here:

Toshiba A68KSM696X
Toshiba A68LTF356X
Beijing-Matsushita A68MAU085X90
Beijing-Matsushita A68LZU185X


Unless one of these was a Net City or Naomi Universal "converted" into NNC and not labeled properly (the A68KSM696X was a Nanao MS-2933 so I'm suspicious), I presume the NNC bezel will fit any of these tubes, correct?

All of these would have the same dimensions and the same neck pinout (B10-277 board), so would it be safe to say that any of these A68*** monitors is suitable for a tube-swap so long as I keep the yoke, neck-board, and chassis that came with the NNC?

From my limited research into tube-swapping that seems to be all that is needed, but all the videos and explanations I've seen were dealing with 15khz monitors only.

Does a tri-sync monitor have anything special within the tube itself that requires additional consideration here? Or is the difference between a 15khz and 31khz display merely in the yoke and the chassis that drives it?

Lastly, are there any known Toshiba PF consumer sets with tubes that would be a suitable replacement in a NNC?

I see there are still a few sources where one can buy a "A68LZU185X" tube, though curiously it appears to be branded as Phillips . Is this common for different manufacturers to use the exact same model number like this, and would I need to worry about differences in mounting brackets, etc?

Sorry for the barrage of questions
 
Nothing special in the tubes for trisyncs, apart from ostensibly being high pitch enough to actually resolve 480p content. Often VGA-resolution monitors have yokes with different impedances than typical SDTV-resolution monitors, but there's no written rule about it.
 
Hatsune Mike said:
Nothing special in the tubes for trisyncs, apart from ostensibly being high pitch enough to actually resolve 480p content. Often VGA-resolution monitors have yokes with different impedances than typical SDTV-resolution monitors, but there's no written rule about it.
Click to expand...
So I could use a let’s say Astro city tube with tri sync or 31 kHz chassis ?
 
So the rule of thumb is: if the impedance levels are within +/- 10% of the measured values on the current yoke, it may not necessarily work but at least it won't blow up your chassis if you try it?
 
I hope most chassis will have some self protection, but that's my rough rule of thumb. It's worth a shot if the specs aren't totally out of wack.

I've had some situations where it seems like it should be perfect, and yet still something is off. One example is that the Toshiba chassis from the New Net City won't be able to properly focus an MS8/MS9-29 tube. Maxed out, the focus is just okay. It needs a higher focus voltage, and that's not something that can be trivially changed.
 
The focus is probably an issue with the flyback, not the yoke, right? Perhaps the shape of the tube is also a factor (NNC has "pure flat" Toshiba monitors and Ms8 is a different shape IIRC)
 
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