CIRCLOTRON

The name Circlotron is derived from the schematic representation of the amplifier output stage, where the bridge circuit is drawn in a circle... A Circlotron is a vacuum tube power amplifier with an unusual push-pull output stage. Rather than alternately driving halves of an output transformer primary whose center-tap is connected to B+, a Circlotron drives the entire primary from a floating bridge. Originally, Circlotron was an Electro-Voice (EV) trademark, these days it seems to refer to any amplifier with a bridged output stage and floating power supplies... The invention of the Circlotron amplifier has generally been generally attributed to Alpha M. Wiggins of Electro-Voice, Inc., Buchanan, Michigan. Wiggins' patent application for the amplifier was filed on March 1, 1954. However, several other inventors filed patents prior to Wiggins. Cecil T. Hall of Mount Lebanon, Pennsylvania filed a patent for the Circlotron output topology on June 7, 1951. Tapio Köykkä of Finland also..