| 摘要 |
<p>1,236,994. Analogue multipliers. INTERNATIONAL BUSINESS MACHINES CORP. 1 Aug., 1968 [1 Sept., 1967], No. 36653/68. Heading G4G. [Also in Divisions G3 and H3- H5] An electronically variable impedance element, Fig. 2, comprises a phase reversing amplifier 5 having an input impedance, a feed-back impedance R# and an impedance 13, Rs shunting the input is characterized in that one of the impedances, e.g. transistor 13, is voltage variable in a linear manner by control signal 14. In an analogue multiplier, Fig. 10, the element 60 is arranged as a resistance which is connected to a current source 64 which constitutes one of the two signals, A, to be multiplied. The other signal, B, is constituted by source 68 which is connected to transistor 67 to control the value of resistance 60.</p> |
