Electronic Circuits Projects Diagrams Free - Electronic Theory http://www.electro-tech-online.com/ Basic principles, ideas, concepts, laws, and formulas behind electronics. en Fri, 20 Nov 2009 22:01:15 GMT vBulletin 60 http://static.electro-tech-online.com/images/misc/rss.jpg Electronic Circuits Projects Diagrams Free - Electronic Theory http://www.electro-tech-online.com/ identifying the correct point of Ic(sat) http://www.electro-tech-online.com/electronic-theory/100188-identifying-correct-point-ic-sat.html Wed, 18 Nov 2009 13:12:48 GMT i am doing an experiment on the dc characteristics of the BJT and have drawn the output characteristic curve for values of IB=20uA and IB=50uA (Refer... i am doing an experiment on the dc characteristics of the BJT and have drawn the output characteristic curve for values of IB=20uA and IB=50uA (Refer to attachment)

In order to find the beta of the transistor, I take Ic(sat) / Ib.
Referring to the 2 points of the graph i have circled in the attached pic, which point should I take for Ic(sat)? The point where the curve starts to become horizontal [black box] or the point right at the end (highest point of Ic) [red box]?

help is extremely appreciated. thanks=)
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]]> Electronic Theory qtommer http://www.electro-tech-online.com/electronic-theory/100188-identifying-correct-point-ic-sat.html Power = ½ V² / R ? http://www.electro-tech-online.com/electronic-theory/100050-power-v-r.html Sat, 14 Nov 2009 18:58:07 GMT I sometimes see in some places that power is defined as ½ V² / R. Where does the ½ come from? I sometimes see in some places that power is defined as ½ V² / R.

Where does the ½ come from? ]]> Electronic Theory alphacat http://www.electro-tech-online.com/electronic-theory/100050-power-v-r.html Horizontal vs Vertial Polarization http://www.electro-tech-online.com/electronic-theory/99841-horizontal-vs-vertial-polarization.html Mon, 09 Nov 2009 22:57:57 GMT If I'm not mistaken most television broadcast chanels are vertically polarized, yet all the yagi's I see on rooftops are horizontally polarized, can someone explain this? ]]> Electronic Theory Sceadwian http://www.electro-tech-online.com/electronic-theory/99841-horizontal-vs-vertial-polarization.html simple idial ressistor question.. http://www.electro-tech-online.com/electronic-theory/99753-simple-idial-ressistor-question.html Sat, 07 Nov 2009 12:39:11 GMT a simple resistor ( which is designated as broken line) has 2 ohms why we say it linear and time invariant. the function of the resistor if ... a simple resistor ( which is designated as broken line) has 2 ohms
why we say it linear and time invariant.
the function of the resistor if
f(t)=2

f(x+y)=2 but f(x)+f(y)=4
additive therefore its not linear.

where is my mistake? ]]> Electronic Theory transgalactic http://www.electro-tech-online.com/electronic-theory/99753-simple-idial-ressistor-question.html graph sum question.. http://www.electro-tech-online.com/electronic-theory/99751-graph-sum-question.html Sat, 07 Nov 2009 12:19:42 GMT http://i34.tinypic.com/bi10z9.gif i cant understand how they sum those three graphs. when we sum graph 2 and 3 we get graph 3 lifted by a certain... http://i34.tinypic.com/bi10z9.gif
i cant understand how they sum those three graphs.
when we sum graph 2 and 3 we get graph 3 lifted by a certain number.
but when we add graph 1 to the result
on point where the current is 0 the voltage is from 0 to -infinity.
before that current 0 that is no points,so on that section it cannot affect the
result graph
but it does .
why? ]]> Electronic Theory transgalactic http://www.electro-tech-online.com/electronic-theory/99751-graph-sum-question.html components graph question.. http://www.electro-tech-online.com/electronic-theory/99750-components-graph-question.html Sat, 07 Nov 2009 12:04:55 GMT http://i38.tinypic.com/xdxsuv.gif 1. i know that a diode is short circuit when the currect threw it is positive and open circuit other wise ... http://i38.tinypic.com/xdxsuv.gif

1.
i know that a diode is short circuit when the currect threw it is positive
and open circuit other wise

but the graph of it says
when the current goes from zero till infinity
the voltage is zero (which is fine)

but
that on current 0 the voltage goes from zero till minus infinity

what does it mean " zero till minus infinity"?

i cant see how it means open circuit

2.
why a battery gives a constant voltage no matter the current? ]]> Electronic Theory transgalactic http://www.electro-tech-online.com/electronic-theory/99750-components-graph-question.html physical explanation question.. http://www.electro-tech-online.com/electronic-theory/99586-physical-explanation-question.html Tue, 03 Nov 2009 19:41:33 GMT why when when we connect capacitators in a row(not paralel) the capacitance gets smaller i need the physical explanation for it why when when we connect capacitators in a row(not paralel)
the capacitance gets smaller

i need the physical explanation for it ]]> Electronic Theory transgalactic http://www.electro-tech-online.com/electronic-theory/99586-physical-explanation-question.html Fourier transform and Laplace transform http://www.electro-tech-online.com/electronic-theory/99270-fourier-transform-laplace-transform.html Tue, 27 Oct 2009 00:58:53 GMT I'm not very sure if this is the right forum to post this, but didn't find a better one.

I would like to know if the Fourier transform can always be achieved by finding the Laplace transform, I'm asking because I find in a Signals & Systems book, a problem that said Find the Fourier transform using the Laplace transform, well, actually it was the solution manual, and what they did was find the Laplace transform and change S for jω. Is that always possible? ]]> Electronic Theory Karkas http://www.electro-tech-online.com/electronic-theory/99270-fourier-transform-laplace-transform.html <![CDATA[Thevenin's Theorem Practice]]> http://www.electro-tech-online.com/electronic-theory/99126-thevenins-theorem-practice.html Fri, 23 Oct 2009 16:13:47 GMT Hey Everyone,

I'm terrible when it comes to Thevenin's Theorem, so I'd like some practice. Does anyone know of links or PDFs that contain a complete explanation or Thevenin's theorem and also numerous practice problems?

I'd appreciate it!

Austin ]]> Electronic Theory ElectroNerdy http://www.electro-tech-online.com/electronic-theory/99126-thevenins-theorem-practice.html