Assertion: oscilloscope's control | /r/HasProperty | the source
Facets:
Source sentences:
text: The principal controls of this section are the source and coupling selector switches, and an external trigger input (EXT Input) and level adjustment.
text: The primary and principal controls of trigger section are the source and the coupling selector switches.
text: The principal controls of this section are the source and coupling selector switches, and an external trigger input (EXT Input) and level adjustment.