Using PPM Meters on a Professional Radio Desk

1. Keep the channel fader DOWN
2. Switch the channel’s ON button on. (If it has one).
3. Press the PFL button down.
4. Press play from your source or speak into the microphone. (Make sure you are in a comfortable position in front of the mic and speak at your normal volume.)
5. Look at the meters on the right-hand side of the desk.
6. Use the gain button at the top of the channel to adjust the source/voice until the meters peak at 0. (We go to 0 on this desk)
7. Switch off the PFL button (so that the button is UP).
8. Open the fader to 0 on the desk
9. Press play from the source/start speaking into your microphone.

Read more here:
https://www.onlineradioschool.com/radio-training-videos/master-the-mixing-desk-like-a-professional-radio-dj