| 摘要 |
761,331. Transistor pulse circuits. PHILIPS ELECTRICAL INDUSTRIES, Ltd. Nov. 17, 1954 [Nov. 20, 1953], No. 33293/54. Class 40(6) In a circuit for converting a train of pulses of the same sign into a train of positive and negative pulses, the pulse train is fed to a transistor frequency divider which returns pulses of larger amplitude but of opposite sign to produce the desired pulse train in the input circuit. Positivegoing pulses a from generator 1 are applied to point contact transistor 4 having a circuit 5 tuned to a subharmonic in the base lead to provide positive feedback, the incoming pulses synchronizing the oscillations. The amplitude of the generated pulses b is such that when added to the pulses a, the desired train c is obtained. These pulses may be converted by transistor 7 to the waveform d. The transistor 4 need not be in an oscillatory state but may be arranged to be triggered into an unstable state by the pulses a. The circuit 7 may be self-oscillatory and synchronized by the pulses c. If the frequency of circuit 5 is a lower subharmonic, equal numbers of positive pulses will occur, separated by single negative pulses, the output wave d having long and short pulses in alternation. |
