【摘 要】
：
顾名思义,这种测试器无需拆下印刷板上的晶体管,就能判断晶体管的好坏。图示为测试器的电原理图。图中多谐振荡器的振荡频率为1KHz,其输出端与D双稳触发器连接,D触发器输出
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顾名思义,这种测试器无需拆下印刷板上的晶体管,就能判断晶体管的好坏。图示为测试器的电原理图。图中多谐振荡器的振荡频率为1KHz,其输出端与D双稳触发器连接,D触发器输出的互补方波(Q和Q端)频率为500Hz。D_5和D_8分别为红色和绿色发光二极管(LED)。测试时由Q和Q端的分压来驱动晶体管的基极。在不接晶体管时,由于两只LED的开关频率为500Hz,所以,LED轮流闪烁。若连接
As the name implies, this tester does not need to remove the printed circuit board transistor, you can judge the transistor is good or bad. The schematic shows the electrical schematic of the tester. In the figure, the oscillation frequency of the multivibrator is 1KHz, the output of the multivibrator is connected to the D flip-flop, and the frequency of the complementary square wave (Q and Q terminals) output by the D flip-flop is 500Hz. D_5 and D_8 are red and green light-emitting diodes (LEDs) respectively. Test by the Q and Q-side voltage to drive the base of the transistor. In the absence of transistors, the two LED switching frequency of 500Hz, so the LED flashes. If connected
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