Living Dead

It definitely recognizes that a cartridge has been inserted, because it loads a black screen every time. Take it out and the BIOS screen comes right back. Something I didn't think to do was to try to start a game even though the screen is black, like maybe it has music but no video. Regarding your comment, how could I determine if "U5 is constantly outputting an active select on one of the cartridge lines?" Thank you for the suggestions so far. I will try them. I already tried cleaning the cartridge slot, but I only used canned air to blast it out. I'll try alcohol next.

So my wife just acquired her childhood ColecoVision, and it's in really nice shape with the steering wheel, the super action controllers, tons of carts with overlays, you name it. When I turn it on, the screen displaying COLECOVISION loads just fine and is crystal clear with a modern A/V cable. However, any game I put into the cartridge slot just loads a black screen. I know the games are good... I have another working Colecovision and I tested them in that machine. So my question for folks more skilled than myself is where do you start in diagnosing and fixing an issue like this? Can the cartridge slot go bad while everything else remains functional? Most the tutorials I've seen for black screens just show that the system doesn't power on at all, but that is not the case here. I am a total amateur when it comes to these things... all I've ever done is replace capacitors in a Sega Master System. Any advice would be appreciated. If this issue is discussed elsewhere, I apologize for overlooking it.

I've sent a PM about some problems I'm having. Probably will require your services.

Any news on the Harmony Concerto?

I'm wondering the same thing. Came here to buy the Harmony, but then started reading about Concerto. Guess I'll wait, but for how long?