If your ActivPanel does not show an image after connecting an external device or an OPS but there is a "No Signal" message on screen, please follow the steps below for your relevant source type.
"No Signal" on external source
Ensure the desired source is selected on the panel. You can confirm this by pressing the source button on the remote control or the panel. Also, ensure the cable from the computer is plugged into that source on the panel securely. It should not wiggle or fall out easily.
Confirm your computer is set to a compatible screen resolution.
If previous steps have been confirmed, your computer is connected properly to the ActivPanel. Try these other steps if the “No Signal” message still persists.
Connect directly to the ActivPanel if you are using an indirect connection such as a wallbox, adapter, etc.
Try another HDMI port. Be sure to switch sources afterward.
Try another HDMI cable — preferably one that works currently on another computer.
Test another computer on the ActivPanel.
"No Signal" on OPS source
Press the source button on the panel or remote and confirm it is set to OPS.
If the "No Signal" message still persists, ensure the OPS is installed properly. Remove it and carefully slide it back into place.
Watch this video to learn how to remove it safely.
Slide the OPS back in its slot, tighten the screws and turn the panel back on.
Then press the SOURCE button on the remote control or the panel and select the OPS source.
https://www.youtube.com/watch?v=LefuVA0QV8I
https://support.prometheanworld.com/s/article/2416?language=en_US