Hey! I have a (vintage!!) Roku LT and i just got a new television (a 43'' Insignia, not a Smart TV). I haven't used the Roku for a while, but it's not damaged or anything. However, I can not get it to show up on the TV. I'm using the AV cord, I'm in AV input mode, and everything is plugged in. Is it possible that they just aren't compatible?
Definitely are compatible.. I'd try the Roku on another TV just to be sure it's still functional. Could be a dying power supply, could be in a video mode not supported by your TV..
Make sure that if it's plugged into AV1 (for example) that that's the source you've selected on the TV.
Also, once it's on, do you get any sound of you hit the home button or arrow buttons a few times? In other words, is it a video problem only or also audio?
Make sure they're plugged in correctly.. I've plugged component and composite cables in with little to no light and later noticed to reversed a cable.