在图12-4中，正确的输出信号表达式为：（）。https://assets.asklib.com/psource/2015110117304062529.jpg

A . 30，24 B . 24，30 C . 28.2，22.2 D . 28.2，24

A .https://assets.asklib.com/psource/2015110110334621588.jpg B .https://assets.asklib.com/psource/2015110110340299751.jpg C .https://assets.asklib.com/psource/201511011034175015.jpg D .https://assets.asklib.com/psource/2015110110343034391.jpg

A . L=A+B B . L=AB C . L=0 D . L=·B+·A

A .https://assets.asklib.com/psource/2015110110064980810.jpg B .https://assets.asklib.com/psource/201511011007091323.jpg C .https://assets.asklib.com/psource/2015110110072370179.jpg D .https://assets.asklib.com/psource/2015110110073874078.jpg

A .https://assets.asklib.com/psource/2015110110025279724.jpg B .https://assets.asklib.com/psource/2015110110030684500.jpg C . [https://assets.asklib.com/psource/2015110110032459544.jpg ]D .https://assets.asklib.com/psource/201511011003398932.jpg

(5) A．X+Y B．XY C．X⊕Y D．<img src='https://img2.soutiyun.com/ask/uploadfile/4872001-4875000/9f2eb8c49195b103e3f6e0e6bbecb313.jpg' />+Y

在图16.26所示电路中,已知<img src='https://img2.soutiyun.com/ask/2020-10-06/970865523313676.png' />,试求输出电压u。 <img src='https://img2.soutiyun.com/ask/2020-10-06/970865474211867.png' />

<img src='https://img2.soutiyun.com/ask/2020-10-07/970950087816858.png' /> <img src='https://img2.soutiyun.com/ask/2020-10-07/970950104521813.png' />

<img src='https://img2.soutiyun.com/shangxueba/ask/18489001-18492000/18491351/2015110114454662221.jpg' /> A．6 B． 9 C． 12 D． 5

在图题4.4.5所示的电路中，Uo为正弦波小信号，其平均值为0,BJT的β=100。(1)为使发射极电流IEQ。约为1mA,求Re的值;(2)如需建立集电极电位VCQ为+5V，求Rc的值;(3)R=5kΩ,求AVS。电路中的Cb1和Cb2的容抗可忽略，取Rs=500Ω <img src='https://img2.soutiyun.com/ask/2020-06-28/962211111166418.jpg' />

<img src='https://img2.soutiyun.com/shangxueba/ask/66444001-66447000/66446309/978107420603847.png' />

<img src='https://img2.soutiyun.com/shangxueba/ask/18090001-18093000/18091211/2015110117304062529.jpg' /> A．Y=A B． Y=1 C． Y=0

<img src='https://img2.soutiyun.com/shangxueba/ask/18366001-18369000/18366604/2015103016200329921.jpg' /> A．<img src='https://img2.soutiyun.com/shangxueba/ask/18366001-18369000/18366604/2015103016201852323.jpg' /> B．<img src='https://img2.soutiyun.com/shangxueba/ask/18366001-18369000/18366604/2015103016203316643.jpg' /> C．<img src='https://img2.soutiyun.com/shangxueba/ask/18366001-18369000/18366604/2015103016204578274.jpg' /> D．<img src='https://img2.soutiyun.com/shangxueba/ask/18366001-18369000/18366604/201510301620588928.jpg' />

A．u(t)=U_m[1+mcos(Ωt)]cos(ω_ct) B．u(t)=U_mcos(Ωt)cos(ω_ct) C．u(t)=U_mcos[ω_ct+mcos(Ωt)] D．u(t)=U_mcos[ω_ct+msin(Ωt)]

在图11.4.4所示的电路中，输出电压uo为()。 <img src='https://img2.soutiyun.com/ask/2020-07-01/962444859976237.png' /> <img src='https://img2.soutiyun.com/ask/2020-07-01/962444868545727.png' /> A.uI B.-uI C.-2uI

在图10-6非对称式多谐振荡器电路中,已知G₁和G₂为74系列反相器7404,它们的输出高电平<img src='https://img2.soutiyun.com/ask/2020-12-25/977745494489401.png' />,输出低电平<img src='https://img2.soutiyun.com/ask/2020-12-25/977745585165587.png' />阈值电压<img src='https://img2.soutiyun.com/ask/2020-12-25/977745593373057.png' />输入钳位电压<img src='https://img2.soutiyun.com/ask/2020-12-25/977745603765651.png' />,内部电阻<img src='https://img2.soutiyun.com/ask/2020-12-25/977745616267366.png' />给定R=1.5kΩ,C=0.01μF,试求电路的振荡频率. <img src='https://img2.soutiyun.com/ask/2020-12-25/977745644900004.png' />

<img src='https://img2.soutiyun.com/ask/uploadfile/5475001-5478000/1fcbe47aa95e01157c9899c6474fddbe.png' />

<img src='https://img2.soutiyun.com/ask/2020-09-14/968971604757546.png' />

在图NP2-17(a)所示的T型匹配网络中，已知输出负载电阻为R_L，放大器要求的匹配阻抗为R_e。 <img src='https://img2.soutiyun.com/ask/2021-02-24/983011823810775.png' /> <img src='https://img2.soutiyun.com/ask/2021-02-24/983011845538018.png' />

在图12.4.1所示的半波整流电路中，变压器二次侧电压22的有效值为U，则整流电压平均值U为()。 <img src='https://img2.soutiyun.com/ask/2020-07-01/962445064917959.png' /> A.0.9U B.0.45U C.U