Is the video cable composite or s-video? the output from the receiver to the sets line input (1,2,3,s-video) must be the same on most receivers. If the game console uses composite (yellow rca connector) to the receiver, the same cable must be the same from receiver to TV. Some receivers do "up convert" to s-video or to Progressive scan (red,green,blue rca connectors) and do not follow this rule. Yor set needs to be switched to the correct input as well. None of the receivers I have services thus far hve the 75ohm cable lug for RF. Check all the cableing and repost if you find something new or different.
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