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    Good Resource For Learning Bjt Transistors And Amplifier

    You are not going to learn in a few hours, knowledge which takes several lectures and many days of study and practice to assimilate. You should tell your instructor that you are hopelessly behind your class, and either drop out or delay your test if you can. Ratch
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    Ebers Moll model art of electronics

    A simple differentiation. Temperature is in kelvin units. The Early effect is modeled by a resistor between the collector and base. Some of the current is shunted by that resistor. Read another source for a different or better explanation. Ratch
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    2N3055's and heat

    If you peruse post #5 in this thread, you will see a circuit that uses a power resistor to dissipate most of the heat, thereby lowering the heat sink requirement. Ratch
  4. R

    2N3055's and heat

    What instance? Did the OP say what his needs were? Perhaps a switching regulator is too noisy for his application. Ratch
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    Element table question...

    Adding or removing another proton to the nucleus of an atom is a major change to the nucleus. It increases or decreases the atomic number and weight of the atom. Why do you think that is such a wonderment? Surely you do not expect the same element to have a varying weight and atomic number...
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    2N3055's and heat

    You might want to study post #2 of this link. http://www.electro-tech-online.com/threads/bullet-proof.146490/#post-1240701 . Ratch
  7. R

    Element table question...

    Yes, you are reciting the periodic table, but what is your question? By the way, chemical elements are not capitalized. Ratch
  8. R

    Element table question...

    You are missing a good clear definition of your question. Do you mean that 1 comes before 2, and 2 comes before 3, etc? Could you better explain your question? Why do you call it a "puzzle"? Ratch
  9. R

    RCRL equivalent

    You cannot convert that circuit to another configuration like a star or delta because it will only be valid at one frequency. That is because the reactances of the L and C change with frequency so that each frequency requires a component value change. You can find the impedance between "a" and...
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    Multisim - How do I find the Resonant Frequency (FR) on an LRC circuit?

    You will find parallel resonance a lot more ... interesting. Ratch
  11. R

    How do you connect all the voltages together into one?

    If you had two batteries, you could connect them in series and harness the voltages from each battery into one summation voltage. Is that what you want to do? Ratch
  12. R

    Capacitors

    This is a perfect example of how using technical slang instead of clear descriptive language confuses your understanding of how things (capacitors in this case) work. Even though everyone knows what you mean when you use the slang term "charge", it is still not descriptive of how things work...
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    Electronic math

    Algebra is the least of your needs. You have to know calculus and differential equations to really understand what is happening when doing circuit analysis. You can use a canned method to find the answer to an stock problem, but to really understand what the circuit is doing, some higher math...
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    Multisim - How do I find the Resonant Frequency (FR) on an LRC circuit?

    Try a frequency range, between 700 to 80,000 Hz. Also, plot more points, especially near the resonant frequency, so that you can see the true shape of the current curve as shown below. Ratch
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    Finding C & L from XC and XL

    In a series resonant circuit, the frequency of resonance can be found by inserting a ammeter, and sweeping the circuit with a variable oscillator until the current peaks at maximum. The frequency that causes the current to peak is the resonant frequency. Otherwise, you can find the frequency...
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    Voltage Drop across NPN BJT C&E?

    As said before, Vbe control both Ic and Ib. . Certainly, Vbe controls IC. . Ic changed only 0.07 ma when Vce changed 2.03 volts. Using the definition of resistance we get 2.03/0.07E-3 = 29k ohms. That indicates the BJT is a pretty good current generator. As you can see from the...
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    Voltage Drop across NPN BJT C&E?

    Unless you factor in secondary effects, you will not be able to change Ic while holding Vbe constant, while the BJT is operating in its active region. Look at the BJT data sheets and see how independent Ic is compared to the collector voltage. The BJT is a transconductance device, meaning...
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    Voltage Drop across NPN BJT C&E?

    No, that base current is waste leakage current that comes from the charge carriers that do not make it from the emitter to collector, and are instead lost to the base due to the voltage on the base. It is a phenomenon that can be minimized, but not eliminated. Ib is exponentially proportional...
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    Capacitors

    You are using technical slang when you or anyone else says a capacitor is "charged". The correct description is energized. When a voltage is applied across the cap, electrons accumulate on one plate and deplete by the same amount on the opposite plate for a net change of zero. So even when a...
  20. R

    Voltage Drop across NPN BJT C&E?

    No question about it, the Vbe controls the emitter/collector current. Why? The physics of the BJT show that it does. Without going into great detail, the BJT is a diffusion device whose rate of diffusion is determined by Vbe. Since the emitter/collector current is determined by the...
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