Love your Tenna anatomy posts! If you could, could you explain what kind of circumstance would cause the classic 'bars of bright colors' sort of malfunction in a TV vs a screen full of static?
Of course! The easy answer is that neither of these are malfunctions, although we tend to think of them as such, and instead kind of like the "default" states of television. I'll do their purpose in general and then how we see them with Tenna.
Static (aka digital snow or white noise) is the shortest and easiest to explain. Your television gives this to you because whatever channel you picked doesn't have anything on it, but there is *something* being transmitted anyway that it can't make sense of. After all, not just television uses electromagnetic waves. So since there's no station playing something on the specific signal you tuned to, it's taking random signals from background radiation and trying its best to show it. This won't make a logical picture, though, so we get this random pattern of pixels and electronic noise.
Next, we have SMPTE Color Bars, or...just color bars. We don't need to say that it's the pattern standardized by the Society of Motion Picture and Television Engineers every time, after all. This was developed as a form of calibration for analog screens like Tenna, and nowadays is used to calibrate external monitors that we connect to cameras so multiple people can look at what's being recorded (such as the director and producers) without crowding around the camera operator. Every bar is a main color at 100% intensity, ordered in a specific way that makes sense if you go through every way to calibrate a screen and that is a lot to go over which I don't think is needed info, but you want it, looking for SMPTE calibration will get you where you're going. It also plays a really annoying sound that you may know as the censor noise, because you'll KNOW if it's too loud and adjust accordingly.
Also quick fun fact, the "technical difficulties" screen that Tenna flashes by is based on the old, black-and-white version of that. When we say technical difficulties with the color bars now, it's probably because your television is fine, but there's something wrong on the end of the people transmitting. If you're not calibrating the television and the colors pop up, it's an issue with the source signal.
Now, let's look at when this happens with Tenna. I found one major place where he has static, and one major place he has color bars.
In Tenna's final boss fight, he gets the static every time you select a minigame and he's using his own head as a transition to it. You could say that he's initially getting static because he's between channels, since that happens sometimes as little "blips" as you're changing them. It could also be that the signal he's turning to doesn't have anything broadcasted on it until he decides so by teleporting the gang into that area. I'm more of a fan of the latter, since that means that he has direct control over electronic signals, not just the ones he listens to, and that better explains how he transports the gang into the minigames: he transforms them into information that he decodes on his screen.
And of course, we have the prime example of him using the color bars...when he dies. I'd like to note that the stuff coming out of his arms looks a lot like static, although I don't have any reason for saying it other than I think it looks cool. So, this is often used as a modern "technical difficulties" screen, and it can easily just be that. It can also be Tenna trying to recalibrate himself. He realizes there's a problem and is running diagnostics instinctively. Obviously, there is nothing that checking color values can do for losing your arms, so this doesn't do anything to help him.
If he is theoretically both the receiver and transmitter of his own signal, this could also be him showing that he lost his source. Maybe his source signal is whatever keeps him alive as a Darkner, analogous to how we are kept alive by our hearts beating and electric activity in our brains? If he is making his own signal, that can also be how he physically moves the gang to the channel he broadcasts the minigames in, and him experiencing a large amount of pain/damage would be reason to conserve energy and not do it anymore.