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Scared of bjts

  1. Mar 10, 2009 #1
    okay for some strange reason i'm very very scared of bjts .. i dont know maybe i just dont get em at alll... is there some site or some book that explains bjts in the simplest terms??
    u know something crude that gives u the basics??
  2. jcsd
  3. Mar 10, 2009 #2
    What don't you understand about them? Basically they are just switches. Similar to light switches at home except that bjts can switch on and off millions of time per second.
  4. Mar 10, 2009 #3
    http://www.uoguelph.ca/~antoon/tutorial/xtor/xtor.html [Broken]

    The above might help.

    Last edited by a moderator: May 4, 2017
  5. Mar 10, 2009 #4
    There are some good lecture videos/animations on youtube.
  6. Mar 11, 2009 #5
    i dont know i'm just scared of them.. i read the book and it goes over my head .. OVER my head.. using sedra smith and a systems approach to electronics.... its just confusing... and i spend half the time trying to figure out whats happening to the electrons ...
  7. Mar 11, 2009 #6
    Start here if you are reading from books-
    Art of electronics and Electronic devices by David A.Bell

    Basically its like a vacuum tube. You make electrons in one terminal, you collect them in the other. You insert a 'gate' halfway to control the amount of electrons.
  8. Mar 12, 2009 #7
    Do you mean bjts (bipolar junction transistors), like npn and pnp? Get a 2N3055 and 2 one-watt, 100 ohm resistors. Connect the collector to + 15 volts thru one 100 ohm resistor. Connect the emitter to ground through the other resistor. Get a 1k pot, connect it between ground and + 10 volts, and the wiper to the base through a 1k resistor. Now monitor the collector and emitter voltages and vary the base voltage. Plot the emitter and collector voltages as a function of the base voltage.
  9. Mar 12, 2009 #8


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    I like John Popelish's "drunken bum on a crazy street transistor analogy".

    See the second post here:

    Oh heck, I'll just go ahead and repost it:
  10. Mar 16, 2009 #9
    thanks... reading the bum on a drunken street analogy calmed me down a bit.. enuff to be able to go and hit the books again... i hope i get something this time... :D
    if i dont its back to this thread ...
    :D :D
    thankyou everyone..
    and i'll try getting a pair of bjts and experiment with them soon enuff (Godwilling)
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