Jeff- thanks.
The negative signal on the screen from the projector for an input error is a small x next to the input icon and the font may be yellow. For an operating input, there is no "x" and the projector does its internal adjustment and switches to project based on the nature of the live input.
If an hdmi cable is plugged in input 1 or 2, the projector will allow the input to be selected.
When I tried to fire up the system, the AVR was plugged into input 2 on the projector and the screen showed an input error. I then moved the hdmi from input 2 to input 2 and got the same result.
Trying to eliminate all variables, I pulled out a new 30' hdmi cable and plugged it directly from the OPPO disc player to input 2, same dead input result. With a non UHD disc, Input 1 was fully operational. With a UHD feed, the screen, presumably driven by the OPPO, told me that the TV was not compatible with the signal.
So then I went to the AVR and plugged the OPPO back into the Blu-ray input and the new HDMI into the primary HDMI out on the Dennon. Same story: Input 2 on the projector showed error, input 1 allowed all but UHD to display.
With this, I then went to the AVR and turned every input on to test that. XBox worked not problem, even showed 4K output to screen through Input 1.
The Dish Joey plugged into "CBL/SAT" or HDMI 1 on the Dennon triggered an input error on Input 1 on the screen so I plugged the HDMI to the projector directly into it and the screen fully projected the images. I moved the Dish feed from HDMI 1 to 2 on the Dennon and tried the projector in the main output and it worked fine.
So my summation from this is that HDMI 1 on the Dennon is dead and Input 2 on the Projector is dead, possibly because of some surge or other from the Dish feed. Strangely, the Dennon AVR was on when I got there and may have been "on" for a week or three. I'm usually very good about turning it off but one of the kids may have left it on. Equally, could have been me.
Does that help? And, again, thank you very much for the input.
DDM