I have a first generation, Mitsubishi VS-50800, which I hooked up to the DTC*100 using a VGA to BNC cable. I am using it with Directtv and am unable to get a picture at all, I just get a message "No video signal detected". I have tested the DTC-100 with a computer monitor, and am receiving a picture. What am I doing wrong? Is there an activation for this input? I'd really appreciate some help.