Display Constantly Dropping Component Video Signal

[R9Ragnarok]

Greetings all! I'm experiencing some strange behavior with outputting component video from my MiSTer. I've not seen any discussion describing similar behavior, so I have to reach out to my MiSTer family in hopes someone else has an idea of what is happening.

A few months back I was blessed by the god of glowing phosphors and found a nice looking Sansui DTV2798A on the curb waiting to be taken away to the dump. My favorite hobby as of late has been combing my local area for any and all CRTs I could perform RGB mods on, so I pulled the car over and took a look. Was seriously surprised to see the manufacture date on the back of this bubble screened beauty was 2008. Immediately knew all hopes of RGB modding were dashed, but it had component inputs so I decided to bring her home. Once back home I fire it up, and she powers on.

I ran the new TV through its paces testing each video input option. I have one of the s-video/composite adapters from Antonio Villena. Both composite input 1, 2, and s-video are working great. Finally time to see this thing really show me what its capable of check out component video. Here immediately things got strange.

The boot screen and initial OSD menu come up and for a split second, everything is looking great. Then the screen goes black and the TV is proclaiming no signal. The main menu then comes back up for a moment, then again we lose signal. The pattern starts of maybe 5 seconds of picture, then 5-10 seconds of the TV reporting no signal. Want more weirdness?

I finally get somewhat frustrated and walk away for a moment to think. I come back a few minutes later, and the TV is displaying the gray static screen solid, and its not losing sync. I watch it for a few minutes, and the TV is not dropping signal. I grab my controller and bring up the menu thinking the earlier behavior was a fluke. As soon as I pull up the MiSTer's OSD menu, the TV immediately loses signal. I have no idea why, but I can tell you that various screens and conditions cause this TV to lose the component signal. Here's a quick list of things observed.

-MiSTer boot screen will lose signal as long as the OSD is on screen. As soon as the OSD times out, the TV happily keeps signal and displays the full screen static screen

-All MiSTer cores loaded and idle cause the TV to lose signal EXCEPT the NES core.

-I have been able to blind navigate and launch various games from various cores. It seems like the display losing signal varies wildly with what kind of screen the game is displaying. When a game starts its main game play, the display seems to be ok with that and will display the game. Title screens, transition screens, just about anything that isn't the main game play, the TV will just be a black screen with a no input message. If a game is displaying, pulling up the MiSTer's OSD will make it drop signal again.

-It doesn't make any sense to me, but I feel like I'm seeing a pattern of excessively black screens causing a drop in signal. Jotego's beta of the Sega Sytem 16 and Golden Axe are good examples. It will lose input when I load the game, but the signal and picture will return when the game starts and shows the title screen. The intro cycles through quick character descriptions for each character and it does a transition where the screen turns black. Every time this occurs, I lose signal to the TV. It will get signal again after the transition ends.

-Seemingly again related to mostly black screens, as I said the NES core is the only core I can load and let sit idle and it will not lose signal. Its also loads a gray screen at launch instead of the standard black screen. The Gameboy and GBA core will also display picture for a moment when they load, but will quickly drop signal. It really seems to be that they don't have a completely black screen at boot/idle.

Logic says you found the TV by the side of the road...there's a reason it was thrown out. True enough, but I got off my ass and dug out my old faithful modded original Xbox with component cables and enjoyed several hours of flawless performance last night. The XBox signal never dropped once.

The next likely culprit would be bad settings in my .ini. Well, I'm fairly well versed in the different video output options of the MiSTer, and have used just about everything. I have a Toshiba 27af43 that loves the component output from the MiSTer. It looks amazing and has never had any issues with the signal dropping.

I can provide video examples of this behavior if requested. I'm just at a loss as to what the issue is. I imagine it might just come down to the fact that this display doesn't like what the MiSTer has on tap. Just wondering if anyone out here in the MiSTerverse has experienced anything similar or could offer any insights.

[dunning_kruger]

Did you ever find a solution to this? I have the exact same TV and am experiencing the same things with component input.

[FoxbatStargazer]

I kind of blame the Mister device here, there's been issues with a number of TVs losing sync over component when hitting very bright or dark screens. Haven't heard of any solutions though and it may well be a hardware issue.

Only thing I'd say is if you got your I/O board from aliexpress or the like then it's kind of suspect, especially for component output. You can either buy from a more local Mister seller or maybe swap the flakey capacitors if you're truly adventurous, other threads (purple tint on component) have more details.

[Wave]

I kind of blame the Mister device here, there's been issues with a number of TVs losing sync over component when hitting very bright or dark screens. Haven't heard of any solutions though and it may well be a hardware issue.

This brief lose-sync issue is observable via RGB as well as component, in my experience.

A recent discussion on Reddit actually has some interesting new tidbits that suggest possible hardware-level remedies in the future. (I'm linking deep into the thread but there is discussion before this, too.)

Dunno if the more serious-sounding "completely lose sync over component" issue from the OP is a more serious manifestation of the brief lose-sync problem (could well be) or another problem altogether.

[dunning_kruger]

Thanks wave!

I was able to Swap R1 (1K) with a 330 ohm resistor. It wasn’t a surface mount resistor, but it worked. So far I’ve tested for like 5 minutes, but I’m optimistic.

https://github.com/MiSTer-devel/Hardwar ... rd_6.1.pdf

[Wave]

Oh, glad to hear!
Maybe keep us updated on how you fare over the next while. Hopefully it resolves everything.

If you have access to an RGB display, you could also check if you get the Reddit person's "slightly too blue" look in RGB output.

[dunning_kruger]

I will keep y’all posted. I honestly didn’t think this was going to get anywhere. When I found this post I was reminded of this https://xkcd.com/979/

[dunning_kruger]

I’m 9 hours into FF6 and everything is working great.

[Wave]

Great!

If anyone also wants to test the resistor mod with RGB input, it'd be great to hear if you can reproduce the original Reddit user's "slightly blue" result.