摘要 |
An inductor included as part of a pulse width modulation amplifier is formed by four coils 9A, 9B, 9C and 9D arranged alongside each other and connected in parallel. The coils are supported against electromotive forces tending to pull them together by insulating strips 10. The coils are enclosed within an electromagnetic shield formed by a cabinet 1. Because of the arrangement of the coils the magnetic field generated by them is confined to a region in the close vicinity of the coils, so that the losses which would otherwise occur as a result of the proximity of the shield or other cabinet are reduced to a minimum. Thus the efficiency of the inductor formed by the combined coils is greater than would be the efficiency of a single coil within the same cabinet, this latter arrangement being conventional. |