Squegging

Squegging is a radio engineering term. It is the abbreviation of self-quenching. A squegging or self-blocking oscillator produces an intermittent or changing output signal. Wildlife tags for birds and little mammals use squegging oscillators.^[1] The Armstrong super-regenerative radio receiver uses a self-blocking oscillator, too. The receiver sensitivity rises while the oscillation builds up. The oscillation stops when the operation point no longer fulfills the Barkhausen stability criterion. The blocking oscillator recovers to the initial state and the cycle starts again.^[2] The receive frequency of the Armstrong Super-Regenerative receiver was some hundred kilo Hertz. The self-quenching frequency was ten kilohertz, just above the highest audio frequency the headphone could reproduce.

Squegging is an oscillation that builds up and dies down with a much longer time constant than the fundamental frequency of the oscillation. A self-quenching oscillator circuit oscillates at two or more frequencies at the same time.

Unwanted squegging

In an amplifier, squegging is unwanted. Squegging in a vacuum tube audio amplifier is called motorboating because it sounds in the loudspeaker like a diesel engine in idling rotational speed.

Patents

• US 3782730, Horchler, Stephen A., "Golf Ball", published Dec. 2, 1971, issued Jan. 1, 1974 
• US 1424065, Armstrong, E. H., "Signalling system", published June 27, 1921, issued July 25, 1922 

References