An all-magnetic audio amplifier system
J. J. Suozzi, Edward T. Hooper · Transactions of the American Institute of Electrical Engineers Part I Communication and Electronics · 1955
ALTHOUGH magnetic amplifiers have been used as audio amplifiers, the necessity of generating the high carrier frequency has made their use impractical. The objection to the use of rotating machinery to produce this carrier is the mechanical problem introduced by moving parts, while the use of the vacuum-tube oscillator as a high-frequency source introduces the disadvantages of fragility, short life, and increased maintenance problems. Although switching transistors associated with saturable reactors can be used to produce a high-frequency carrier, problems of performance and reliability arise because of the early stage of development.