Advice on Coleco Gemini black screen?

[azure]

I recently picked up a Gemini, but it displays a black screen and produces no audio. I think it's probably the VIC chip (Coleco's version of the TIA), because both video and audio are affected. If not, then could it be something with the RF modulation?

I know the power adapter works. I tested it on an Atari 2600. The power input jack was loose so I reflowed the solder on that. The screen goes from static to black screen on power up, so I know something is happening. I have a multimeter but I'm not sure what to look for.

 

I could grab a VIC chip from a ColecoVision expansion module or maybe just get another Gemini. I'd rather reap an expansion module, because they seem to be cheaper and more common than Gemini consoles. My console is very clean and I got it cheap, so I'd like to fix it instead of selling it for parts. Before I buy something I was wondering if there's something else I should check. Maybe capacitors?

 

I looked over the board and chips very closely and saw no oxidation, no breaks in the traces, and no obvious loose parts. I should mention when I got the console it had 3 metal screws bouncing around inside the case. The screws were not from the Gemini, so someone probably dropped them inside the cartridge opening. They would have been bouncing around during shipment and I wonder if the shipper might have shorted something out by plugging it in for test.

 

Got any suggestions?

 

(RF cover removed by me.)

 

Edited August 18, 2019 by azure