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Nanao chassis, Hitachi tube?

NFGx

NFGx

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I received two Super Neo 29 Candy cabs today, and I'm excited to get them up and running. The seller shipped them with the original Hitachi A68LFP227X tubes, but said that the Toshiba chassis were dead and he was including a pair of Nanao MS9 chassis instead.

But... The connectors are different. The Hitachi tube uses very small pins. I've seen someone selling adaptor wiring, which certainly suggests that they're directly compatible, but I can't find anything from anyone who's actually done it.

Aside from that problem, the cabs are in astonishingly good shape, and one came with a bagged English manual. The only scans I've seen online are in Japanese. Does the English scan exist, or should I get to scanning?
 
These probably came with Hitachi GMK-29FSx chassis originally?

I would probably just snip off the original connectors and replace them with MS9 compatible ones. Suitable JST equivalents are linked to here. Demag coil and tube ground use the same connector series as the horizontal yoke connector.
 
I'm well on the way to getting this done. My original question was as much 'can I expect this to work?' as 'the pins are different'. So far no one's said it's a bad idea to try, so I'm gonna.

RGB, degauss and power inputs are done. Since the chassis also supports separated sync (I didn't know any of them did!) I've also wired in a VGA connector.

I don't have a compatible plug for the degauss connector on the PSU, so that's on hold. And it's not easy to find a NEMA 120V cable in Australia that'll work with the Candy's power supply, but I've got one or two I can sacrifice until a replacement arrives.

I hope to do a trial run later today.
 
Thanks for that link.

I popped the MS9 into the Candy, and got a stable image first try. The pincushion is really bad on both chassis, and neither chassis will focus well - but one is slightly better than the other. I'll be sending them off for a service, and working out a pincushion plan for when they return.

(Got any tips?)
 
There's a pot for adjusting pincushion on the chassis, SPC15. Did that not help?
 
nem said:
There's a pot for adjusting pincushion on the chassis, SPC15. Did that not help?
Click to expand...
I actually had no idea this pot existed. I've never had to work on the geometry on my cabs. That will definitely be easier than the horrors of tiny magnets I was envisioning. ^__^

The chassis' are on their way back to me after a refresh. I hope to get back to these monitors this week.
 
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An update to this story: the MS9 chassis' have arrived and I've wired them all up (with some additional connectors mailed up from Melbourne by a generous soul on FB). The pincushion was indeed easy to solve, the problem now is that one of the tubes is a bit dim, and they both cannot be made very bright at all without huge amounts of focus loss (ie: blur) and significant horizontal bleed.

I was assured these chassis would work on the Hitachi tubes, but I'm starting to suspect the tubes themselves are shot. Unless someone can give me any other ideas about the blur problem? They are only sharp when the image is almost too dim to see. Making it bright enough to play, or as bright as I want it, makes it increasingly blurrier. And I know about the focus pot on the flyback. It's cranked all the way to the end of the dial (whether that's min or max I do not know) and then up about a 16th of a turn and it becomes legible but not clear. Anything above that is just worse.
 
Is there a heater resistor that needs changing if a Hitachi tube is uses with a Nanao chassis? There is a thread about this somewhere at Arcade Projects.
 
thegreathopper said:
Is there a heater resistor that needs changing if a Hitachi tube is uses with a Nanao chassis? There is a thread about this somewhere at Arcade Projects.
Click to expand...
Well, the only mention of this tube on this forum is this thread, so... ¯\_(ツ)_/¯
 
Copied from an old post.

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.

https://www.arcade-projects.com/threads/yoke-and-tube-specs-for-monitors.9819/page-5#post-323474
 
Well I've got two of these Hitachi tubes, one is brighter than the other, with the same MS9 chassis. So if you're suggesting the heater being too cool makes the image dim, that doesn't seem to be a chassis problem, but a tube problem.

If that's not what you're suggesting then I'm sorry, I really don't know what the linked post is suggesting beyond "some tubes need different heater voltage". =/
 
Your other tube just has better emissions.

Try changing the heater resistor. It will help with both tubes, one of them will just see a bigger improvement.
 
nem said:
Try changing the heater resistor. It will help with both tubes, one of them will just see a bigger improvement.
Click to expand...
Will it help the focus though? That's the bigger problem at the moment.
 
Will it help? I don't know. Can it help? Yes.

You're not losing anything with trying. It's a 50 cent resistor.
 
NFGx said:
I received two Super Neo 29 Candy cabs today, and I'm excited to get them up and running. The seller shipped them with the original Hitachi A68LFP227X tubes, but said that the Toshiba chassis were dead and he was including a pair of Nanao MS9 chassis instead.

But... The connectors are different. The Hitachi tube uses very small pins. I've seen someone selling adaptor wiring, which certainly suggests that they're directly compatible, but I can't find anything from anyone who's actually done it.

Aside from that problem, the cabs are in astonishingly good shape, and one came with a bagged English manual. The only scans I've seen online are in Japanese. Does the English scan exist, or should I get to scanning?
Click to expand...
Hey mate, super pumped about these recent acquisitions to your collection 👊

Hoping the image problems have a reasonable outcome (Wish I was closer to help out).

The only place I know the scans may exist is the Hard Candy website https://www.hard--candy.com/
However there appears to be zero English scans for any Super Neo 29. Yours would be most welcomed I am sure!

(Does the website curator have an account here that we can ping them on?)
 
NFGx said:
Will it help the focus though? That's the bigger problem at the moment.
Click to expand...
If I remember correctly I remember someone on another forum i'm on testing a Hantarex Polo 3 chassis on a TV crt and changing the heater resistor did help with the focus in some cases.
 
An update to this saga:

I took the tubes to a CRT guy who gave 'em a blast with the rejuvenator. The gauge showed that all three guns on each tube were really close to 'good' but after a couple of seconds with the machine, they were much clearer. One of them's basically come good, the other still has a lot of blooming on the blue gun.

Come January I'm going to drop them off for him to try and dial in a little better. He's one of those old techs who lived and breathed CRTs back in the day and he's confident he can make 'em work.

So the heater may still come into play, but for now I got 70% of the way there with the rejuve. ^__^
 
Just as an interim post, someone messaged me asking about the details of the swap, so I thought I'd add some info here:

In terms of geometry and functionality, it's a good match.

The Hitachi uses two small pin deflection connectors, the Nanao uses one big and one small.
The Hitachi uses two ground wires to the neck board, the Nanao has one pin.
The Hitach degauss connector was also small, so that needs a swap.
 
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