240p composite to CRT TV artifacts blurry text dots

jmandawg

Hi all,

I found a 32" CRT on the side of the road, so of course i hooked my RPI up to it using the 240p setting in the config.txt. Everything looks pretty good, but i'm getting some weird artifacts which is making text hard to read. It's like extra pixels (electrons on CRT) are turned on. Anyone have any idea how to fix this?

Here are some pics:

Text in black Tiger seems to have white dots under it
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Text in Contra
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Ladders in donkey kong
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chipsnblip

hi jmandawg,

glad you were able to adopt the CRT and give it a new home :)

i'm going to take a guess and say those are just artifacts from a composite cable connection.

i can highly recommend you try out the custom configs that @Sakitoshi has put together.

if you're still having issues after that, fire up a 240p test suite rom (preferrably snes or genesis) and take a few photos of the grid pattern to show the folks in the CRT Gaming reddit group. that TV in getting old and might just need some electrolytic capacitors replaced. either way, have fun with it - it can become a great hobby project.

hope this helps at least to point you in the right direction. happy new year!

dankcushions

looks to me like the game is running in the wrong resolution. what emulator?

240p signal is being sent, as it has scanlines, but the wrong resolution is running in the emulator so there are scaling artefacts. either the game you're running is not 240p, or it's including overscan or something else that is distorting the image.

i would personally not use those custom configs - they're not true 240p as such.

jmandawg

Thanks guys. I posted on Reddit and they suggested messing with the service menu. And I got it better by modifying the c-trap setting.

https://www.reddit.com/r/crtgaming/comments/abt1fv/240p_composite_to_crt_tv_artifacts_blurry_text/