Is that okay to bias a transistor like this?

Discussion in 'Homework Help' started by asdf arfw, Nov 19, 2017.

  1. asdf arfw

    Thread Starter Member

    Sep 9, 2017
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    http://tinyurl.com/ybvwgmnw
    Should I put some resistors between +5v and Vc? I just want to amplify currents to let LED works because I don't know the value of resistor between +5v and Vb if it's too high the LED won't work at all so I put the transistor to make sure it still work in that case.
     
  2. DickCappels

    Moderator

    Aug 21, 2008
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    The LED only needs a resistor and a voltage source. The transistor only adds un-needed components. Trust me.
     
  3. dl324

    AAC Fanatic!

    Mar 30, 2015
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    Image in question (edited):
    upload_2017-11-19_9-3-13.png

    If this is homework, what is the purpose of the problem?
     
  4. MrChips

    Moderator

    Oct 2, 2009
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    Depends on what you are trying to do.
    If you want the LED to just stay on, use a resistor and LED alone. Omit the transistor as Dick says.
     
  5. asdf arfw

    Thread Starter Member

    Sep 9, 2017
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    http://tinyurl.com/y7pkf7gd
    Okay, I should give you more information about my school project.
    I actually designed my own measurement water level and the problem is the water isn't a good conductor at all and its conductivity isn't constant depends on where I took the water from. So when I put it in the water my LED won't work at all. I decide to use transistors to amplify currents to make sure it still works when the conductivity of water is too low. I want to know is that okay to bias a transistor like I posted on the top because
    the current from Emitter is the highest and I want to use it for my LED but I never saw someone bias a transistor like that before.
     
  6. DickCappels

    Moderator

    Aug 21, 2008
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    Yes, not a problem.
     
  7. asdf arfw

    Thread Starter Member

    Sep 9, 2017
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    Appriciate, thanks a lot!
     
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