Hello- I have a formerly working Atari 7800 that recently stopped working. I am not longer getting a video signal output. The power LED on the system itself is lighting up and I've measured the voltage where the power supply connects to the circuit board and that is fine. No obvious signs of electronic component failure. Tried plugging it into more that one TV with different RCA cables all with the same result. Does anyone have any suggestions for repairs? Any good troubleshooting web sites that any of you are aware of? Thanks for any help you can provide.