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This page contains all the sets of general questions about circuit properties I have created so far (under construction). I number and date them consecutively as they have appeared in my mind; then, I arrange the questions systematically of circuit evolution - passive > transistor > op-amp etc.
I began implementing this column a year ago as a flash movies; after I had created the first nine questions I temporarily stopped the column. If you want to view these flash versions, click the fuchsia colored questions.
In order to know more about the topic discussed, copy the question name from the table below, paste it in the subject field, add additional questions in the message body and e-mail me. Your e-mail will not be automatically answered; I will prepare every e-mail answer especially for you revealing the circuit phenomena in a catchy and exciting manner. Thus you will get unusual and original explanations of the circuit properties that you have never seen before!
The circuits from this page are also presented in the constant e-mail circuit columns circuits, questions, paradoxes, lessons and in the weekly updated circuit columns paradoxes (flash animated), contradictions, conflicts, principles, building schemes. Browse through these pages and ask questions!
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Number/Week |
Subject |
Circuit Questions |
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Passive Circuits: Sources, Conductors, Loads ... |
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|---|---|---|
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Question 39 February 14, 2005 |
Passive versus active circuits | What do passive circuits really do? And what do active circuits really do? What is the difference between passive and active circuits? And v.v., in what way are they alike? |
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Question 40 February 21, 2005 |
Capacitors, inductors ... | Do the capacitors and the inductors dissipate energy? What do they really do? Do both the passive and the active circuits dissipate energy? |
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Question 41 February 28, 2005 |
Passive versus active circuits | Is it possible that a passive circuit should contain transistors? Can a transistor act as a passive element? And v.v., can a resistor act as an active element? |
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Question 42 March 07, 2005 |
Passive circuits and sources | Can a passive circuit contain electric sources? If yes, will this passive circuit become an active one? |
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Negative Feedback Followers |
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Question 19 September 27, 2004 |
Active copying (negative feedback principle) | What does a man do when he keeps within certain limits his body position and weight, speech level, good spirits, health and property status, constant car velocity and direction etc.? May we generalize all these situations into a block diagram? What is an operation of copying (following)? What is an operation of active copying? |
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Question 20 October 04, 2004 |
Negative feedback (active) follower | What is a follower? What is a passive follower? What is an active (negative feedback) follower? Do you see any connection between the active follower and the man behavior generalized in the block diagram showed? What is a block diagram of an active follower? How do we make follower? How do we build step-by-step an active follower? |
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January 26, 2004 |
Emitter follower | What is a general idea behind an emitter follower? What does the transistor do in this circuit? Do you see any connection between the emitter follower and the man behavior generalized in the block diagram showed? How do we build step-by-step an emitter follower? |
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February 02, 2004 |
Source follower |
What is a general idea behind a source follower? What does the FET transistor do in this circuit? Do you see any connection between the source follower and the man behavior generalized in the block diagram showed? How do we build step-by-step a source follower? |
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February 09, 2004 |
Op-amp follower | What is a general idea behind an op-amp follower? What does the op-amp do in this circuit? Do you see any connection between an op-amp follower and the man behavior generalized in the block diagram showed? How do we build step-by-step an op-amp follower? Is it absolutely nessesary to use here an op-amp with a differential input? May we use an op-amp with single-ended input? |
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Question 21 October 11, 2004 |
Op-amp inverter | What is a general idea behind an op-amp inverter? What does the op-amp do in this circuit? What is a virtual ground? Why is this circuit inverting? Do you see any connection between an op-amp inverter and the man behavior generalized in the block diagram showed? How do we build step-by-step an op-amp inverter? Is it absolutely nessesary to use here an op-amp with a differential input? May we use an op-amp with single-ended input? |
| Negative Feedback Followers Disturbed | ||
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Question 22 October 18, 2004 |
Negative feedback follower disturbed |
What does the man keeping the entities within certain limits (see Question 19) do when a harmful disturbancies stays in his way? |
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Question 23 October 25, 2004 |
Emitter follower input disturbed |
What does the transistor do in the circuit of emitter follower when we vary the input voltage? Do you see any connection between the emitter follower disturbed and the man behavior generalized in the block diagram of an active follower? Does the transistor act as a man? |
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Question 24 November 01, 2004 |
Emitter follower supply disturbed |
What does the transistor do in the circuit of an emitter follower when we vary the supply voltage? Do you see any connection between the emitter follower disturbed and the man behavior generalized in the block diagram of an active follower? Does the transistor act as a man? How do we use this phenomenon to build a constant voltage source? |
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Question 25 November 08, 2004 |
Emitter follower load disturbed |
What does the transistor do in the circuit of emitter follower when we vary the load? Do you see any connection between the emitter follower disturbed and the man behavior generalized in the block diagram of an active follower? Does the transistor act as a man? How may we use this phenomenon to build a constant voltage source? |
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Question 26 November 15, 2004 |
Emitter follower collector disturbed |
What does the transistor do in the circuit of emitter follower when we put a collector resistor Rc and begin varying its resistance? Hint: Imagine that Rc is the resistance of a long line. Is the resistor Rc harmful element? May we use this phenomenon to build a useful circuit? |
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Question 27 November 22, 2004 |
Op-amp follower input disturbed | What does the op-amp do in the circuit of an op-amp follower when we vary the input voltage? Do you see any connection between the op-amp follower disturbed and the man behavior generalized in the block diagram of an active follower? Does the op-amp act as a man? |
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Question 28 November 29, 2004 |
Op-amp follower supply disturbed |
What does the op-amp do in the circuit of an op-amp follower when we vary the supply voltage? Do you see any connection between the op-amp follower disturbed and the man behavior generalized in the block diagram of an active follower? Does the op-amp act as a man? How may we use this phenomenon to build a constant voltage source? |
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Question 29 December 06, 2004 |
Op-amp follower output disturbed |
What does the op-amp do in the circuit of an op-amp follower if we put a resistor to the output and connect the negative feedback loop before the resistor? How does the op-amp react if we move the feedback loop after the resistor? Does the op-amp act as a man? Is this phenomenon harmful or useful? May we use it to build some popular circuit? |
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Question 30 December 13, 2004 |
Op-amp output protective resistor hidden |
May we connect 100 Ohm protective resistor in the op-amp output so as to retain the zero output circuit resistance? |
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Question 31 December 20, 2004 |
Remote voltage sensing |
How to make a constant voltage source (voltage stabilizer) keeping a stable voltage across a remote load? How to make the op-amp react to the varying load distance? |
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Question 32 December 27, 2004 |
Op-amp output resistance decreased |
Why the op-amp follower/inverter has an almost zero output resistance while the bare op-amp has some resistance (typically 100 Ohm)? |
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Question 33 January 03, 2005 |
Op-amp follower load disturbed |
What does the op-amp do in the circuit of an op-amp follower when we vary the load? Do you see any connection between the op-amp follower disturbed and the man behavior generalized in the block diagram of an active follower? Does the op-amp act as the man? How may we use this phenomenon to build a constant voltage source? |
| Negative Feedback Amplifiers | ||
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Question 34 January 10, 2005 |
Negative feedback amplifier |
May the man acting as a follower disturbed (see Question 22) become an amplifier? |
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Question 35 January 17, 2005 |
Common-emitter amplifier |
May we convert an emitter follower into a common-emitter amplifier? If yes, how to do that? |
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Question 36 January 24, 2005 |
Op-amp non-inverting amplifier |
May we convert an op-amp follower into a non-inverting amplifier? If yes, how to do that? |
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Question 37 January 31, 2005 |
Op-amp inverting amplifier |
May we convert an op-amp invertor (k=1) into an inverting amplifier (k>1)? If yes, how to do that? |
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Question 38 February 07, 2005 |
Op-amp inverting voltage divider |
May we convert an op-amp invertor (k=1) into an inverting divider (k<1)? If yes, how to do that? |
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Parallel Negative Feedback Circuits (Versus Passive Circuits) |
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October 13, 2003 |
Ammeter | What does the op-amp do in the circuit of the active ammeter? Is there any relationship between a bare ammeter and an active ammeter? How do we convert a simple ammeter into an active one? |
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October 20, 2003 |
Current-to-Voltage Converter | What does the op-amp do in the circuit of the active current-to-voltage (I-to-V) converter? Is there any relationship between a passive and an active I-to-V converter? How do we transform a passive I-to-V converter into an active one? |
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October 27, 2003 |
Resistance-to-Voltage Converter | What does the op-amp do in the circuit of the active resistance-to-voltage (R-to-V) converter? Is there any relationship between a passive and an active R-to-V converter? How do we transform a passive R-to-V converter into an active one? |
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November 03, 2003 |
Current-to-Voltage Capacitive Integrator | What does the op-amp do in the active current-to-voltage capacitive integrator? Is there any relationship between a passive and an active I-to-V C integrator? How do we transform a passive I-to-V C integrator into an active one? |
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November 10, 2003 |
Current-to-Voltage Inductive Differentiator | What does the op-amp do in the active current-to-voltage inductive differentiator? Is there any relationship between a passive and an active I-to-V L differentiator? How do we transform a passive I-to-V L differentiator into an active one? |
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November 17, 2003 |
Current-to-Voltage Logarithmic Converter | What does the op-amp do in the active current-to-voltage logarithmic converter? Is there any relationship between a passive and an active I-to-V log converter? How do we transform a passive I-to-V log converter into an active one? |
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November 24, 2003 |
Op-amp Inverting Amplifier | What does the op-amp do in the circuit of the op-amp inverting
amplifier? Is there any relationship between a voltage divider and an inverting amplifier? How do we transform a passive voltage divider into an active one? |
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December 01, 2003 |
Parallel Negative FeedbackCircuits | What does the op-amp do in all these op-amp circuits with parallel negative feedback? Is there any relationship between the passive and the active versions? How do we transform passive circuits into active ones? |
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December 08, 2003 |
Resistance-to-Voltage Converter | What does the op-amp do in the circuit of the active resistance-to-voltage (R-to-V) converter? Is there any relationship between a passive and an active R-to-V converter? How do we transform a passive R-to-V converter into an active one? |
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December 15, 2003 |
Voltage-to-Voltage Capacitive Integrator | What does the op-amp do in the active voltage-to-voltage capacitive integrator? Is there any relationship between a passive and an active V-to-V RC integrator? How do we transform a passive V-to-V RC integrator into an active one? |
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December 22, 2003 |
Voltage-to-Voltage Inductive ifferentiator | What does the op-amp do in the active voltage-to-voltage inductive differentiator? Is there any relationship between a passive and an active V-to-V L differentiator? How do we transform a passive L differentiator into an active one? |
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December 29, 2003 |
Voltage-to-Voltage Logarithmic Converter | What does the op-amp do in the active voltage-to-voltage logarithmic converter? Is there any relationship between a passive and an active V-to-V log converter? How do we transform a passive V-to-V log converter into an active one? |
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January 05, 2004 |
Voltage-to-Voltage Inductive Integrator | What does the op-amp do in the active voltage-to-voltage inductive integrator? Is there any relationship between a passive and an active V-to-V LR integrator? How do we transform a V-to-V LR integrator into an active one? |
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January 12, 2004 |
Op-amp inverting summer | What does the op-amp do in the circuit of the op-amp inverting summer? Is there any relationship between a passive voltage summer and an active one? How do we transform a passive voltage summer into an active one? |
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January 19, 2004 |
Parallel negative feedback circuits | What does the op-amp do in all the op-amp circuits with parallel negative feedback? Is there any relationship between the passive and the active versions of these circuits? How do we transform any passive circuit into an op-amp circuit with parallel negative feedback? |
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Last updated February 15, 2005