As well as the 'Art of Electronics' I would strongly recommend:
Wiley: The Fields of Electronics: Understanding Electronics Using Basic Physics - Ralph Morrison
This book also is a great help in understanding how currents flow and how important waves are (as apposed to lazy electrons that just drift along at about 0.1cm per hour), and when AC is present they just jiggle about.
Wiley: The Fields of Electronics: Understanding Electronics Using Basic Physics - Ralph Morrison
This book also is a great help in understanding how currents flow and how important waves are (as apposed to lazy electrons that just drift along at about 0.1cm per hour), and when AC is present they just jiggle about.
Just been looking at some current pulses of square waves on my sim tool, and they go negative on the falling edge, so even though they don't go below zero, the current pulses are positive going for the rising edge and negative going for the falling edge, so the current is reversing direction????
And isn't zero an arbitrary point we pick anyway.
And isn't zero an arbitrary point we pick anyway.
Water/pipe analogies are a good way to start, when you know nothing. They are a bad way to continue, once you know a little. As an EE major you should eventually be able to think in terms of potentials and currents, even if that seems a long way off now.
A tip: when doing circuit theory you should completely forget about electrons and 'conventional current' - just think about sources and sinks of currents of either polarity, and sources and sinks of signals of either polarity and any waveform and frequency. The only exception is that when summing potentials around a loop or summing currents into a junction you need to be consistent in handling polarity.
A tip: when doing circuit theory you should completely forget about electrons and 'conventional current' - just think about sources and sinks of currents of either polarity, and sources and sinks of signals of either polarity and any waveform and frequency. The only exception is that when summing potentials around a loop or summing currents into a junction you need to be consistent in handling polarity.
+1
I have found the the electron billiard ball "explanation" gets deeply mired very quickly once "AC" is introduced.
Get a good grasp of Thevanin's theorem and never lose sight of the rules of conservation of energy is a good mantra for those of us who never worked hard enough to grasp nuclear maths!
I have found the the electron billiard ball "explanation" gets deeply mired very quickly once "AC" is introduced.
Get a good grasp of Thevanin's theorem and never lose sight of the rules of conservation of energy is a good mantra for those of us who never worked hard enough to grasp nuclear maths!
Andrew,
Your point is not quite correct.
1. you could use a transformer.
2. the cap is in fact an integrator.
3. one could use a negative supply on a SE amp make the DC point stable with a servo and still never have the flow through the device "reverse". The current would still only flow in one direction.
And it confuses the issue as to how the active element is functioning.
Which was the OP's main point of confusion.
_-_-
Your point is not quite correct.
1. you could use a transformer.
2. the cap is in fact an integrator.
3. one could use a negative supply on a SE amp make the DC point stable with a servo and still never have the flow through the device "reverse". The current would still only flow in one direction.
And it confuses the issue as to how the active element is functioning.
Which was the OP's main point of confusion.
_-_-
Now we are going to confuse the OP.
OP, Please go to the library and get a basic DC/AC intro book. There is a reason they are several hundred pages long which is why we are not going to provide much in the way of insight here. It will give you a head start on third semester. You should not worry about transistors until you understand passive components and the basic laws.
OP, Please go to the library and get a basic DC/AC intro book. There is a reason they are several hundred pages long which is why we are not going to provide much in the way of insight here. It will give you a head start on third semester. You should not worry about transistors until you understand passive components and the basic laws.
I could ask you to explain all you have stated, but there is no point, in that it would all be based on the fallacy that AC is one direction current flow.
That is where you are wrong.
Alternating current (AC) is reversing of the current flow in alternate half cycles of the waveform.
That is why it is called Alternating Current.
Quite different from Direct Current.
Hi,
As a working definition that is quite wrong, as clearly single supply
amplifiers have no problem handling AC audio signals with a DC
biasing, the source of the OP's confusion, and it's very simple.
AC analysis does not care whether the current reverses or not,
as it always does relative to the static DC current conditions.
rgds, sreten.
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Look up any schematic of a tube amplifier. You'll see there's always a resistor or transformer (I.O.W. a load) connected between the PSU and anode/cathode (the two 'opposing ends'). The tube's amplification properties will only work with this load. Think of it as a variable voltage divider. Look up voltage dividers if you're not familiar. They should first make sense before attempting transistor/tube analysis.
I think it's good you're trying to understand the workings of electronics by means of the given analogies, but they can quickly steer you in the wrong direction. Approaching it a bit more abstract can help in the long run.
P.s. varying DC = AC, superimposed on DC. Connect a capacitor in series, and you'll be left with just the AC.
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