| 摘要 |
<p>The present invention is an electrical circuit for use with a four-pole device. The four-pole device has two input connections and two output connections. The output of the four-pole device is measured at one output relative to a base potential present at the other output. The electrical circuit comprises a two-poled switch, which is connected in such a manner, that in its first position a signal source is connected with the first input of the four-pole device and the output of an amplifier is connected with the second input of the four-pole device. In the switch's second position, the signal source is connected with the second input of the four-pole device and the output of the amplifier is connected with the first input of the four-pole device. The output of the four-pole device, which is at the base potential, is connected to an inverting input of the amplifier, while the non-inverting input of the amplifier is connected to a constant reference voltage (UR). When connected in this fashion, the amplifier serves to compensate base potential present at one output of the four-pole device. The switching arrangement serves to switch the polarity of an information containing component of the output signal of the four-pole device (which depends on the input signal source) without reversing the polarity of an interference component, which is produced within the four-pole device or which is produced in electronic components connected at the output side of the four-pole device. This may be useful for separating the information-containing and interference components in the output signal of the four-pole device.</p> |
