Hi everyone.
I'm a 2nd year electrical engineering student who is making sure to get more involved in the practical side of things rather than just the extensive theory that we cover.
I bought the "All New Electronics Self-Teaching Guide" which has so far been extremely useful. I sometimes get annoyed when for example, the complex arithmetic involved in AC circuits is ignored and instead done in two parts with real numbers (once for the magnitude, once for the angle), but since I can mentally connect the theory and practice, it doesn't bother me. Anyways...
My question involved transistors. Specifically, the book discusses using transistors as high-speed switches controlled by a mechanical switch. When the switch is open and the BJT is OFF, the attached diagram is shown in the book. My question specifically is Why does base have to be grounded (rather then just disconnected) and assuming it is grounded, why is R_2 necessary at all?.
If the switch was open and line was not grounded, there still wouldn't be any base current and therefore the transistor would still be OFF. I don't understand.
Can anyone explain?![Confused :confused: :confused:](data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7)
I'm a 2nd year electrical engineering student who is making sure to get more involved in the practical side of things rather than just the extensive theory that we cover.
I bought the "All New Electronics Self-Teaching Guide" which has so far been extremely useful. I sometimes get annoyed when for example, the complex arithmetic involved in AC circuits is ignored and instead done in two parts with real numbers (once for the magnitude, once for the angle), but since I can mentally connect the theory and practice, it doesn't bother me. Anyways...
My question involved transistors. Specifically, the book discusses using transistors as high-speed switches controlled by a mechanical switch. When the switch is open and the BJT is OFF, the attached diagram is shown in the book. My question specifically is Why does base have to be grounded (rather then just disconnected) and assuming it is grounded, why is R_2 necessary at all?.
If the switch was open and line was not grounded, there still wouldn't be any base current and therefore the transistor would still be OFF. I don't understand.
Can anyone explain?
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