Sine-wave push-pull oscillator circuit, particularly for devices in railway protection engineering

摘要

In a sine-wave push-pull oscillator circuit having a centre-fed parallel resonance circuit (C1, W1, W2), which is connected to the collectors of two transistors (T1, T2), a preamplifier stage (T3, T4), via which a feedback can be adjusted by a common base resistor (R7), is in each case added to these transistors (T1, T2). For this purpose, the base electrode of each preamplifier stage transistor (T3 and T4) is also connected via one resistor each (R5 and R6) to the emitter electrode of the associated transistor (T1 and T2) feeding the resonance circuit (C1, W1, W2). Each of the emitter electrodes is connected to earth potential via an associated low-resistance feedback resistor.