前言 在功率放大电路中,输出级和扬声器之间不用变压器耦合的电路常常被称为“无输出变压器电路”,简称OTL电路。X73就是标准的OTL电路,它是一种乙类单端推挽电路。但是,为了避免交越失真,实际上它是工作在甲乙类状态下。从信号的倒相方式来看,它是属于复合互补对称式推挽电路,因而它是采用两个对称的,不同导电极性的复合管子作推挽输出。 一、电路工作原理 Preface In a power amplifier circuit, a circuit that does not have a transformer coupled between the output stage and the speaker is often referred to as a “no-output transformer circuit” or OTL circuit for short. X73 is a standard OTL circuit, it is a type B single-ended push-pull circuit. However, in order to avoid crossover distortion, in fact it is working in Class A and B states. In terms of signal inversion, it is a composite complementary symmetrical push-pull circuit, so it uses two symmetrical, different conductive polarity composite pipe for push-pull output. First, the circuit works