Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
H03G3/00—Gain control in amplifiers or frequency changers
H03G3/20—Automatic control
H03G3/22—Automatic control in amplifiers having discharge tubes
H03G3/26—Muting amplifier when no signal is present or when only weak signals are present, or caused by the presence of noise, e.g. squelch systems
H03G3/28—Muting amplifier when no signal is present or when only weak signals are present, or caused by the presence of noise, e.g. squelch systems in frequency-modulation receivers ; in angle-modulation receivers