Another day, another Trinitron

[holmesuser01]

Before you attempt the tube swap, see if the deflection yolk socket is the same on both chassis.

When I did the tube swap in my EXR set, I found that the yolk socket was the same on both. This way, I didnt have to do purity on the replacement setup. I installed the tube with all neck components in place. Only had to adjust the h-stat control.

Best of luck to you.

[YamahaFreak]

I opened up my KV-27S66 today to look at the tube socket and BAM! Fake Trinitron CRT:



For comparison, here is the genuine Trinitron tube in my KV-27S26: (CRT socket is still attached because the set was in operation when I shot this photo!)



The sockets are not the same, so I couldn't change them out even if I wanted to. Turns out the S66 was actually manufactured in 1999, two years after the S26.

This fake Trinitron tube makes me wonder if the S66 is still worth repairing. Were the pictures on these fake ones as nice as the genuine Trinitron CRTs?

[crtfool]

Did that S66 set have the TRINITRON name on it? If it did, then wouldn't that be considered fraud on Sony's part!!??

[YamahaFreak]

The television is certainly a Sony Trinitron set, and even the Trinitron label on the back of the CRT tube is authentic.

The labels on both tubes appear legit. Here's the fake Trinitron's label:



And here's the label on the genuine tube:



As you can see, virtually identical except for the CRT part numbers.

On a somewhat related note, are all aperture grille CRTs also one-gun CRTs? As in, would a Mitsubishi Diamondtron CRT also have a single-gun emitter?

[old_tv_nut]

Originally Posted by YamahaFreak

On a somewhat related note, are all aperture grille CRTs also one-gun CRTs? As in, would a Mitsubishi Diamondtron CRT also have a single-gun emitter?

Sony was stretching the concept when they called the Trinitron a "one-gun" tube. It was a three-beam tube like all others, but some of the electrodes were common to all three beams. None of these had a single emitter.

[YamahaFreak]

Originally Posted by old_tv_nut

Sony was stretching the concept when they called the Trinitron a "one-gun" tube. It was a three-beam tube like all others, but some of the electrodes were common to all three beams. None of these had a single emitter.

Maybe I should have worded that differently.

Rather, were the other Trinitron-like tubes more like a traditional in-line tube, or did they have a gun design similar to that of the Trinitron?

[old_tv_nut]

Originally Posted by YamahaFreak

Maybe I should have worded that differently.

Rather, were the other Trinitron-like tubes more like a traditional in-line tube, or did they have a gun design similar to that of the Trinitron?

Scratching my head a bit to try to recall - later non-Trinitron tubes often had common electrode voltages (except for the cathodes, which got separate RGB drive), but I'm not sure if any had a series of common electrostatic fields for all three beams the way the real Trinitron did.

Of course, only the Trinitron had the tensioned-grill shadow mask (with a cylindrical contour). All the other in-line tubes had a solid shadow mask, with short vertical slots and even shorter cross pieces defining the ends of the slots.

[YamahaFreak]

Originally Posted by old_tv_nut

Scratching my head a bit to try to recall - later non-Trinitron tubes often had common electrode voltages (except for the cathodes, which got separate RGB drive), but I'm not sure if any had a series of common electrostatic fields for all three beams the way the real Trinitron did.

Of course, only the Trinitron had the tensioned-grill shadow mask (with a cylindrical contour). All the other in-line tubes had a solid shadow mask, with short vertical slots and even shorter cross pieces defining the ends of the slots.

You're right, I do not recall ever seeing any TV sets made around the same time as the late-model Trinitrons that have the vertically flat picture tube. Is a tensioned-grille shadow mask the same thing as an aperture grille?

[andy]

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[freakaftr8]

Darn, I would hane liked to see that. I ditched my 21" diamondtron after the raster went pink.

[old_tv_nut]

Originally Posted by YamahaFreak

Is a tensioned-grille shadow mask the same thing as an aperture grille?

Yes. Regular shadow masks (either triad or in-line) are self supporting, but the aperture grill is made of vertical strips that are under tension. If overheated (by a intense bright white area), the shadow mask "domes" and can lose purity. The aperture grill, because it's under tension to hold the elements straight, doesn't distort until it is really overheated and starts to sag.

By the way, Trinitron grills typically have three very fine horizontal wires across the screen at about 1/4 height, middle, and 3/4 height, to keep the grille from vibrating. Once someone sees these, they may focus on them and find them annoying. If you haven't noticed them, don't try looking unless you want to notice them every time.

[YamahaFreak]

Originally Posted by old_tv_nut

Yes. Regular shadow masks (either triad or in-line) are self supporting, but the aperture grill is made of vertical strips that are under tension. If overheated (by a intense bright white area), the shadow mask "domes" and can lose purity. The aperture grill, because it's under tension to hold the elements straight, doesn't distort until it is really overheated and starts to sag.

By the way, Trinitron grills typically have three very fine horizontal wires across the screen at about 1/4 height, middle, and 3/4 height, to keep the grille from vibrating. Once someone sees these, they may focus on them and find them annoying. If you haven't noticed them, don't try looking unless you want to notice them every time.

My 15" Trinitron computer monitor (trash find, rescued) has these support wires, but only two, about 1/3 and 2/3 up the screen. They don't bother me too much. (That monitor was made in '97, so it must be one of the last ones built with a real Trinitron gun, it's not an in-line gun.) I have yet to discover said support lines inside my 40" Trinitron, even looking very closely against a white screen.

[old_tv_nut]

Originally Posted by YamahaFreak

My 15" Trinitron computer monitor (trash find, rescued) has these support wires, but only two, about 1/3 and 2/3 up the screen. They don't bother me too much. ...

I have yet to discover said support lines inside my 40" Trinitron, even looking very closely against a white screen.

Thanks for the sanity check - I may have misremembered the number of wires. It would make sense to avoid one visible right across the middle.

Not sure what the situation is with the 40"

[site123a]

So, were there a performance difference in picture quality between the newer short gunned Trinitrons and the pre-1997 ones?

[andy]

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