近期市场上销售一种十几元一台的低挡袖珍放音机,其型号不一,但内部结构基本相同,但该类放音机因使用、保护等方面的原因,故障率较高。因无图纸资料,给维修工作带来很大不便,耗时费力。现根据实物绘出电路图如图1所示,供维修此类放音机的人员参考。从电路图可知,该放音机由音频放大和电机稳速两部分电路组成,其中V_1、V_2、V_3组成音频放大电路, Recently sold on the market a dozen of a low-profile pocket-sized player, its models vary, but the internal structure is basically the same, but this type of player due to the use, protection and other reasons, the failure rate is higher. Because there is no drawing information, to the maintenance work brought great inconvenience, time-consuming and laborious. Now draw the circuit diagram according to the kind shown in Figure 1, for maintenance personnel of such playback player reference. As can be seen from the circuit diagram, the player consists of an audio amplifier and a steady-speed two-part circuit, wherein the V_1, V_2 and V_3 compose an audio amplification circuit,