Old CRT hooked up to new Onkyo Receiver.
Hello, I have a gaming setup with 25 different systems hooked up to my Onkyo TX-NR787 receiver and Samsung 4K TV. I want to hook up my old CRT tv to the receiver so I can play light gun games like duck hunt without having to unhook a system and hook it directly to the CRT. This CRT is old and has no AV outputs, I have a RF modulator (if that helps). I know older receivers used to have a Monitor Out port for old crt's, but this receiver does not. The only outputs I can find are the 2 HDMI's, can I use one of them to display on a CRT? I tried using a HDMI to AV cable plugged into the RF modulator but got no picture. I might be overlooking something simple. Thanks for all the help.