Improvements in apparatus for the making of measurements in connection with telephone and telegraph cables

摘要

333,962. Callender's Cable & Construction Co., Ltd., and Brazier, L. G. May 31, 1929. Inductances and capacities, measuring. - Bridge apparatus for measuring the leakance and capacitance of a telephone &c., cable has resistance ratio arms E, F and measurement arms, the latter arms comprising a fixed resistance H shunted by a fixed condenser K, and a variable resistance J shunted by a variable condenser N, the cable M under test being directly connected across the variable measurement arm and no change of connections being thereafter made, the bridge arms being screened in two groups, one group comprising the apparatus meeting at the point A of the bridge and the other the apparatus meeting at the point D, the screens being connected respectively to the points Band C. An adjustable condenser P balances the bridge to earth capacities of the points B and C.