schaltungsanordnung to signaleintastung in transistor gegentaktmodulatoren of converters, in particular kanalumsetzern in traegerfrequenzsystemen using an additional signalmodulators

摘要

Signal pulses with distorted edges reach the line via the carrier frequency systems. The circuit has a channel modulator, and an additional signal modulator to whose first input the signal carrier frequency is supplied. The channel carrier frequency (omega) is supplied to the second input of the signal modulator (SM). In the latter is provided an electronic switch with a transistor (Ts3). - The transistor base is controlled by the source of the d.c. pulses (r) to be switched-in such that the signal modulator is alternately switched on and off. The collector-emitter and the collector-base paths of the transistor are each bridged with a capacitor (C4, C5). If a transistor push-pull modulator is used, it is switched by displacement of the emitter d.c. voltage of its transistors (Ts1,Ts2) by the electronic switch.(4/5)