| 摘要 |
An audio amplifier system is provided including a transformer having a first primary winding that is center-tapped, a second primary winding and a secondary winding. The amplifier system includes a battery backup system by connecting a battery to the center tap of the first primary winding. The second primary winding is connected to a source of alternating current. The output from the secondary winding is rectified and filtered to provide a positive voltage output and a negative voltage output. A complementary symmetry amplifier is provided having a positive voltage power input, a negative voltage power input, an audio signal input and an output. The positive voltage output and negative voltage output are connected, respectively, to the positive voltage power input and the negative voltage power input of the complementary symmetry amplifier. The opposite ends of the first primary winding are alternately grounded to provide excitation of the transformer, with the magnetic flux of the transformer being reversed with each alternation. During AC operation, the first primary winding circuit is open and, during battery operation, the second primary winding circuit is open.
|
