Variable frequency high power signal generator - produces four control signals for four transistors in each of several bridge circuits across load

摘要

The variable frequency high power signal generator, for driving a loudspeaker, resistance heating or driving a vibrating table etc., consists of a control circuit producing sets of 4 control signals (C1-C4) for applying to the bases of the 4 transistor switches (6-9) in each of n bridges (21-2n) driving the load (3). The control circuit consists of a sinewave pilot generator whose rectified output is modulated to variable length pulses which are then passed to the network of gates that construct the 4 control signals. Each bridge has a transistor in one arm and is connected in series diagonally with the other bridges across the load.