Mod a CRT to increase its TVL

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nes.og
Posts: 133
Joined: Sat Apr 04, 2020 7:01 pm

Re: Mod a CRT to increase its TVL

Post by nes.og »

Syntax wrote: Wed Jul 02, 2025 12:21 am
nes.og wrote: Tue Jul 01, 2025 11:21 pm Thanks for the info @vol.2

Does the mod really increase TVL if you use a TVL test pattern or does it just make the scan lines sharper?
Correct, It makes your monitor look like a hi res screen displaying low res content, horrible scan lines.
But kids these days froth on them scanlines. So hence this thread.

Get ready for a page of BS claiming TVL is increased. The only thing increased is the gap between them.
I assumed it didn’t actually increase real TVL or the TVs would have been set this way out of the box. I assumed it would make scan lines sharper as in finer and less visable like a higher TVL tube but maybe “sharper” wasn’t the best way to convey that.

If it makes them stand out more than it is not something I’m interested in since scanlines already really stand out on some tubes especially large ones with have a larger dot pinch. I have a Sony and Misubishi were the scanlines are already distracting.
nes.og
Posts: 133
Joined: Sat Apr 04, 2020 7:01 pm

Re: Mod a CRT to increase its TVL

Post by nes.og »

nes.og wrote: Thu Jul 03, 2025 8:48 am
Syntax wrote: Wed Jul 02, 2025 12:21 am
nes.og wrote: Tue Jul 01, 2025 11:21 pm Thanks for the info @vol.2

Does the mod really increase TVL if you use a TVL test pattern or does it just make the scan lines sharper?
Correct, It makes your monitor look like a hi res screen displaying low res content, horrible scan lines.
But kids these days froth on them scanlines. So hence this thread.

Get ready for a page of BS claiming TVL is increased. The only thing increased is the gap between them.
I assumed it didn’t actually increase real TVL or the TVs would have been set this way out of the box. I assumed it would make scan lines sharper as in finer and less visable like a higher TVL tube but maybe “sharper” wasn’t the best way to convey that.

If it makes them stand out more than it is not something I’m interested in since scanlines already really stand out on some tubes especially large ones that have a larger dot pinch. I have a Sony and Misubishi were the scanlines are already distracting.
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vol.2
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Re: Mod a CRT to increase its TVL

Post by vol.2 »

nes.og wrote: Thu Jul 03, 2025 8:48 am
I assumed it didn’t actually increase real TVL or the TVs would have been set this way out of the box. I assumed it would make scan lines sharper as in finer and less visable like a higher TVL tube but maybe “sharper” wasn’t the best way to convey that.

The author of this thread and his followers use a definition of TVLs that encompasses the effect of this mod. Luke referenced technical white papers written by television engineers that count the TVLs in such a way that it includes the spot size of the electron beams decreasing towards the minimum dot pitch of the phosphors. Once you hit the phosphor spot size, decreasing the spot size any more makes the moiré pattern visible in the raster because at that point it's smaller than the size of the shadow mask holes/slots/grill.

So Luke and others would argue that it does increase TVLs. I suggested that they revise the terminology but they were dead set against it (especially Luke). I think the point of using TVLs was to garner more attention for it, and it sure worked. I kind of don't like when people do stuff like that though; I would prefer that things are done in the most unsensationalized way possible. That keeps people more level-headed when it comes to expectations, and it doesn't get a bunch of inexperienced people to do dangerous things with the promise of improving their image quality.

But that didn't happen. As it stands, I don't think many people are talking about this anymore because it's a known quantity now. Once all the attention disappeared, Luke moved on; said he only likes tube TVs now or something. Go figure.
nes.og
Posts: 133
Joined: Sat Apr 04, 2020 7:01 pm

Re: Mod a CRT to increase its TVL

Post by nes.og »

Thanks for sharing. I’ll work on doing the mod and using the TVL test pattern before and after to see if the count changes.
LukeEvansSimon
Posts: 129
Joined: Mon Aug 17, 2020 7:28 pm

Re: Mod a CRT to increase its TVL

Post by LukeEvansSimon »

Image
(Click image for full size)

I occasionally check back in on this thread and chuckle when I see that there are still people that are digging in their heels claiming the G1 mod doesn’t work. They don’t understand the tech, and are incapable of inventing anything novel or making any contributions to the CRT gaming community. But they still complain a lot about those who do understand the tech and who make contributions.

Here are good side-by-sides for G1 mod paired with an RGB mod: https://www.reddit.com/r/crtgaming/s/GgxAffAcTd

Anyway, you can buy pre-made mod kits now. I am not affiliated with the seller and I don’t make any money from its sales, but just wanted to contribute to the community, so check out the kit:
https://www.rgbmods.com/products/g1-mod-kit

Here are videos showing how it is installed:
https://youtu.be/USRP-l8v0b4
https://www.youtube.com/live/25vA804P3k4
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