High frequency pulsating electronic signal:
-
Morse code, SOS signal transmission
-
SOS signal reception, Morse code
-
White noise
-
Low frequency pulsing and humming signal
-
High frequency signal
-
Horrifying throbbing low-frequency rumble
-
Morse code transmission
-
Electronic signal, energy buildup
-
Interference Broadcasting
-
High frequency squeak
-
Low-frequency rumble, high-frequency squeak
-
Radio noise
★★★★★