ベクトル表示交流ブリッジ平衡検出装置

抄録

In detecting the balance of A.C. bridge, it is much convenient if the balance detector indicates not only amount but also both of amount and phase of the unbalanced voltage. The most conventional method which shows both of them is by vector indication. An apparatus of vector indication was constructed in which the unbalanced voltage is divided intoX and Y components by a pair of balanced modulators operated by two reference voltages whose phases are led from same bridge source and are different by 90° each other. The two components are connected to the two pairs of deflection plates of a Brown tube.
The vector of the unbalanced voltage of A.C. bridge shows a decided locus correspond to the change of the value of a given bridge element. Some advantages obtained are as follows:
(1) The process to reach the ultimate balance is clearly recognized on its way.
(2) The bridge element and its direction and amount of the change necessary to get the balance can be easily found.
(3) There are some cases that of the two balance conditions, which generally exist in A.C. bridge, one necessary balance condition can be obtained even though the other unnecessary condition is not fully satisfied. (4) By the time constant networks which are placed next the balanced modulators, cosiderable improvement on S/N is made.