The first step to programming a memory channel is in the SR-94HPC is to find the button that is assigned to the memory function (MEM). If you do not see it, quickly press and release the FUNC button until you see MEM.
To add a frequency as a memory channel, press and hold the button that's assigned to MEM (P1 in the picture above).
You will then have the option to choose which memory channel to save the frequency on. If the channel is flashing, that means it's already in use. Once you've selected a channel, press and hold the MEM button until you return to the main screen.
To choose a frequency that was saved to your memory channel, press and release the MEM button. If you see an M like in the picture above, you know you are selecting one of your memory channels. Now rotate the channel selector to scroll through your memory channels until you arrive on the one you would like to use. To go back to regular channel mode, press and release the MEM button.