Connecting to PHON.
Open PHON, switch the Web Remote on in its window, then use Copy token there and paste it above. The token is 32 characters. The button next to it copies a web address instead; pasting that works too, the token is taken out of it. These three settings are shared by every PHON key.
PHON reports the settings of the output it is on and of no other, so a key aimed at a named output stays dark, and refuses the press, while PHON is on a different one.