Where does the saliva for the spit test have to come from?

Even though this rapid antigen test is colloquially called a "spit test", it is not enough to simply spit into the sachet. The virus cannot be detected so easily in saliva only from the mouth. It is therefore important that the saliva for the spit test comes from the deeper throat, because the virus settles in the throat. The best way to get this saliva up is to clear your throat and make a kind of deep "krua" sound.