| 摘要 |
<p>A transformer (90) includes taps (96a, 96b, 96c) by which electrical contact can be made to winding section (90a, 90b, 90c) of the transformer (90) at locations along its length between its end terminals. A first switch (94) permits contact to be made selectively to a selected one of the taps (96a, 96b, 96c). An amplifier (98) has an inverting (-) input terminal, a non-inverting (+) input terminal and an output terminal. The output terminal of the amplifier (98) is coupled to the first switch (94) so that selectively making contact with one of the taps (96a, 96b, 96c) couples the selected tap (96a, 96b, 96c) to the output terminal of the amplifier (98).</p> |
