Connecting 15khz CRT RGB TV via VGA

“640x480” 13.150 640 684 748 836 480 486 489 525 interlace -hsync -vsync

PAL 50: “768x576” 14.750 768 790 859 944 576 581 586 625 interlace -hsync -vsync

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Thanks a lot! It works. It’s great, displaying low quality content, like this ancient rip of the 80s anime ‘Hokuto no Ken’.(3rd post) You really can’t see the compression artifacts.

I also swapped the installation drive into the HP EliteDesk using Intel HD4000 graphics and that too works! (Also incredible how portable Slackware is) Though I have a feeling that the picture quality is worse than with the ATI card.
Can that be - that i.e intel graphics deteriorate in quality at low pixel clocks??
Of course it is propable that this is just a case of placebo effect, it is just hard to objectively compare.

Also will there be resolutions that the Intel graphics can’t display? Could you please provide the console (320p?) modeline. I’m afraid this is where the Intel graphics will fold. I just want to make sure every rom I throw on there works and finally get this retro gaming setup working.

Found both of these TVs in the dumpster: A ‘Thomson 21mg130’ - Made in Poland and the aforementioned ’ FUNAI 20A 1110’ - Made in Italy - at least there is an italian label at the back.

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You can work out the basics of modelines easily out yourself. For example, the 480i modeline I provided

“640x480” 13.150 640 684 748 836 480 486 489 525 interlace -hsync -vsync

Turns into:

“640x240” 13.150 640 684 748 836 240 243 245 262 -hsync -vsync

Or

“320x240” 6.575 320 344 376 416 240 243 245 262 -hsync -vsync

(horizontal values are recommended to be dividable through 8, at least with older drivers, may still work otherwise or automatically adjusted.)

I recommend Windows Custom Resolution utility /WinModelines Windows tools and run through Wine if you want to better understand modeline generation and how to adjust. Or maybe there are good enough online calculators, I don’t use Xrandr (CVT) for modeline generation generally.

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Ok. I have used this online calculator: https://arachnoid.com/modelines/ and it worked fine so far (for CRT monitors). I just don’t know the common TV resolutions and when it’s supposed to be interlaced etc.

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Ah ok, the problem with the GTF standard seems to be that it does result in too low frequencies for TVs, if I enter 640x240@60 Hz it gives me 249 total lines which results in significantly lower hsync (14,94 kHz) than the standard 15,6-7 kHz. It depends on the TV model, it’s possible for some to go under 15 kHz and over, but not by much. You’ll generally want to stick around the middle.

Best thing in your case is probably to try Switchres out. It’s getting too much into basic stuff here otherwise. Use Retroarch’s Rgui for CRTs, it can also be setup for manual use of superwide resolutions like 2560x240, which can be sufficient for NTSC stuff.

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Switchres

Isn’t that only intended for Windows? As far as I’m concerned it’s doing the same thing as the xorg modelines under Linux…

I meant CRTSwitchres in RA.

I’m very sorry for not getting back at you for a very long time. I just kinda lost interest for a while and was to preoccupied with other things. ADHD zoomerism and whatnot. But now I finally got around to getting it working - mostly just checking the switchres option in retroarch.

The intel Haswell HD graphics can go quite low, but not all the way down to native 240p unfortunately, so I have to use superresolution. I don’t know if there is any noticable difference between switchres and native, but it looks perfectly fine to my eyes. Desktop mode is also quite usable at 480p 30hz. It is even viable to watch old anime and movies on the thing. Another older intel mini PC I had couln’t go down to even 480p so it would be unusable for desktop mode.

I installed emulationstation for a nice interface, putting it as autostart so I’m not dependent on a keyboard and it just works great. It runs any emulator installed through RetroArch and the modelines get changed automatically upon starting and exiting RetroArch.

Though I will mention a minor issue I had with the retroarch online core installer. I don’t know if that’s the related with the slackbuild, but I had to set “show unstable builds” in the configuration file, otherwise it would just not display the cores available in the http repo - I also had to 777 the libretro directory in the system library folder where retroarch installs the emulators, otherwise a regular user couldn’t install them.

Remember I pulled up a Thomson ‘21mg130’ and a ’ FUNAI 20A 1110’ out the dumpster. Both 20" tubes. Unfortunately the geometry on both is a bit off. The funai has noticable overscan. On the other hand the Thomson is a bit unsharp and a bit uncentered I think. Adjusting the flyback didn’t do much to fix the sharpness. It also bothers me that on the latter the scanlines aren’t as noticable, so I prefer the funai where the overscan is a bit off, but it’s mostly only noticable in desktop mode - it also has its right speaker not working, but it’s mono anyways, so whatever. The Funai just has a perfectly sharp image and nice clear scanlines. The tube is also much more curved - how it should be.

For trying to fix those geometry issues I opened them up, but couln’t find any geometry adjustment trimpots. Is it really that those cheap consumer TVs don’t have this option or is it only possible to adjust through some hidden OSD menu? I couldn’t find any manuals regarding that. Otherwise I’m happy with the setup. The geometry is not that bad. They are quite recent early 2k models after all.

A little side note. I wonder why on the PS1 games I tested, the picture has little horizontal black bars. Doesn’t bother me much. Just wondering.

Thomson CRT:

Funai:

Guts: (forgot to take pics of the Thomson duh)

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Here’s another post I did a while ago (forgot I had this acc. duh - 2021 was ~3 years ago :fearful:) where I used a 20" computer monitor. It was a pain to set up switch res on that one and the scanlines are unnecessarily thick for my taste. TVs are the way to go. New CRTSwitchRes update

anyways. thanks for reading my blogpost.

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the actual geometry on that funai looks pretty perfect to me, you just have to do some centering, which I think you can do through the modeline if your display doesn’t have a proper service menu.

Can’t get PS2 to work though.

I installed PCSX2 which is called LRPS2 in RetroArch. Bios files are in the correct folder. Games start up, but not much else after that. Klonoa 2 fades in a nice clear Namco logo, but shows only darkness after that. Am I missing something here?

I would try it outside of CRT/modeline stuff first and confirm the behavior. Some games straight-up don’t work with it, some have bugs/errors. Some work fine. Unfortunately, if something doesn’t work, there’s not a whole lot to do about it, as the core is still not very well developed.

Yep. It’s running veeeery slow. There’s some weird glitches going on. right now I can’t get the regular pcsx2 installed, but I’ll look into it.

Btw could this help me output native 240p? The pixel clock would have to go as low as 4mhz for that.

Would be nice to have for some software run without switch res in desktop mode.

AFAIK, if it’s a radeon card that has native analog output (including DVI with the analog pins), it should be capable of outputting low enough res.

Hmm. It’s an MXM card, so I don’t know how it is outputting video since it doesn’t have any video connectors on its own. The Computer I’m planning to put it in has VGA though.

I also found out said computer has an MXM3 port, so I seeked out another offer of a card using an ATI Radeon HD 4570.

I have a Radeon hd6450 that outputs to CRT with crt-emudriver. That’s a second card on a big PC with a primary nvidia Gtx 1070 running win10. Has no vga but dvi, so dvi to vga and scart made by me after reading some diagrams, using a resistor too I think to switch to rgb. Have to switch to radeon as primary before I start retroarch.

Had that funai too some years ago connected to an old Athlon XP and a GeForce mx 400 lol and soft15khz. But funai died. Today I would go for a 20" Philips or Panasonic they have some good tubes if I remember well

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Had some trouble getting PCSX2 to compile on my meme OS. But I just did and it works perfectly fine. The GPU also arrived. I will update when I get it working and if it can hopefully output native 240p. I just need to find a fitting heat sink.

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