There are a good many devices where the power button is a "hard-button" and thus won't have a remote operated power button. However, any remote operated device will have a "play" button on the remote. Some devices have remote operated buttons but no corresponding physical button for that same function on the unit, a common one is "display". Some devices may also have some physical buttons on the dvice, and no corresponding button on it's remote.

Therefore, if the device is remote operated, there may or may not be a power function. But, there will be "transport" and maybe input selection buttons. Your original remote will give a clue if there is a power function or not. Now you just have to hope that if there is one on the oem, they included it in the setup code mapping. "play" for devices like vcr's, cd players, etc is more likely to be remote operated, and more likely to have been mapped. That's why they suggest testing with "play". If play is found, then likely the other transport type functions will work also. Power is a crap-shoot.

Jim