SAP (Services Ancillary to Programme making) includes the use of radio frequencies by independent program producers and other non-commercial broadcasters, with the purpose of providing ancilliary services to the program processing.

SAB (Services Ancillary to Broadcasting) includes the use of radio frequencies by terrestrial radio broadcasters, with the purpose of providing ancilliary services to the program production.

Frequency bands for SAP/SAB, including video links ENG/OB are defined in the Allocation plan.