These satellites could pinpoint the exact location of objects emitting radio signals.
They could even identify the type of emitter, its operational modes, and its activity level.
This function proved valuable for detecting potential military operations by monitoring increased radio communication activity.
By providing early warning of such activity, Tselina offered valuable intel that might not have been obtainable through other means.
[1] Initially divided into "Overview" (Tselina-O) and "Detailed" (Tselina-D), since about 1980 the system has been integrated into a single satellite, Tselina-P,[2] which is also known as Tselina-2.