1. Intercom number 11 2. Keep handset down and press INTERCOM button. 3. Dial 77. 4. Dial the hour, with two digits (e.g. 03 for 3 o’clock). 5. Dial the minutes, with two digits (e.g. 07 if it is now 7 minutes after the hour). 6. Dial 0 for AM or 1 for PM. 7. Press #. 8. Press SP-PHONE