| 摘要 |
The measuring bridge circuit for determining the capacitance and loss-angle of capacitors, consists of a Schering-bridge configuration but with greater accuracy and reduction of errors due to contact resistance. The capacitor under test and adjusting resistor are placed ina circuit which uses operational amplifiers in place of the usual resistance and capacitance decade switches, for determining the complex bridge ratios. - The potential dividers, on the outputs of two of the arms, can be replaced by controlled impedances, such as field-effect transistors. These can be controlled by a digital pulse train whose mark-space-ratio is proportional to the DC control voltage representing the voltage-divider ratio. The measuring bridge can thereby be made automatic.
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