Weekly updated columns: questions - paradoxes - contradictions - conflicts - principles - building schemes
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Every week I add here a little story about paradoxical circuit phenomena in mystery circuits. I number and date these ideas consecutively as they have appeared in my mind; then, I arrange the paradoxes systematically in order of circuit evolution - passive > transistor > op-amp etc. Browse through the list below or just click Current Paradox to find the week's paradox.
I began implementing this column a year ago as a flash movies; after I had created the first nine paradoxes I temporarily stopped the column. If you want to view these flash versions, click the fuchsia colored paradoxes.
In order to know more about the topic discussed, copy the paradox 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 strangeness 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 questions (flash animated), contradictions, conflicts, principles, building schemes. Browse through these pages and ask questions!
| Number/Week | Subject | Circuit Paradoxes |
|---|---|---|
| Sources, Conductors, Loads ... | ||
|
Paradox 16 November 08, 2004 |
Voltage source versus current source | The good voltage source is a bad current source and v.v., the good current source is a bad voltage source. Why? |
|
Paradox 17 November 15, 2004 |
Voltage source versus load | In many electronic circuits voltage sources act as loads and v.v. sometimes loads act as voltage sources. What are these circuits? How do you explain these paradoxes? |
|
Paradox 18 November 22, 2004 |
Current source versus load | In some electronic circuits current sources act as loads and v.v. sometimes loads act as current sources. What are these circuits? How do you explain these paradoxes? |
Paradox 19 November 29, 2004 |
Perfect voltage source versus real one | In some electronic circuits good voltage sources act as bad ones and v.v. sometimes bad voltage sources act as good ones. What are these circuits? How do you explain these paradoxes? |
|
Paradox 20 December 06, 2004 |
Perfect current source versus real one | In some electronic circuits good current sources act as bad ones and v.v. sometimes bad current sources act as good ones. What are these circuits? How do you explain these paradoxes? |
|
Paradox 21 December 13, 2004 |
Sometimes bad voltage source is desired | Most of the car alarm systems include the so called current sensing. In this case, a paradox appears: the worse the car battery is, the better the alarm system works. Why? |
|
Paradox 22 December 20, 2004 |
Conductor versus resistor | In some electronic circuits conductors act as resistors and v.v. sometimes resistors act as conductors. What are these circuits? How do you explain these paradoxes? |
|
Paradox 23 December 27, 2004 |
Ideal voltage load | An ideal voltage load is ... nothing?! But yet, what is it? Compare with an ideal current load!. |
|
Paradox 24 January 03, 2005 |
Ideal current load | An ideal current load is almost... nothing. But yet, what is it? Compare with an ideal voltage load! |
|
Paradox 25 January 10, 2005 |
Voltage load versus current load |
The good voltage load is a bad current load and v.v. the good current load is a bad voltage load. Why? How do we explain these paradoxes? |
| Passive Elements: Resistors, Capacitors, Inductors | ||
|
Paradox 26 January 17, 2005 |
Resistors and energy | Resistors are harmful as they dissipate energy; but yet we use them in electronic circuits. Why? How do we explain this paradox? |
|
Paradox 27 January 24, 2005 |
Capacitors and AC current | A nonconducting dielectric material is placed between the plates of the capacitor; but yet it passes AC current. How do we explain this paradox? |
|
Paradox 28 January 31, 2005 |
Inductors and AC current | A conducting wire is connected between the leads of the inductor; but yet it stops AC current. How do we explain this paradox? |
| Passive Circuits (Converters) | ||
|
Paradox 29 February 07, 2005 |
Simple current source | In order to reduce the obstacle introduced by the nonideal current load connected to the simple current source we ... introduce and even increase another obstacle?!? How do you explain this paradox? |
|
Paradox 30 February 14, 2005 |
Capacitive integrator | Resistors are harmful as they dissipate energy; but in order to reduce the error in the circuit of a passive capacitive integrator we ... even increase their resistance?!? How do you explain this paradox? |
|
Paradox 31 February 21, 2005 |
Potentiometer | A voltmeter measures voltage, an ammeter measures current, a potentiometer measuses ... nothing!? Once it is not a meter why do we say a potentiometer? How do we explain this paradox? | . . . |
. . . |
. . . |
| Amplification | ||
|
December 22, 2003 |
Transistor amplifier | A transistor does not amplify; it just ... attenuates! A transistor is not an amplifier; it is an ... attenuator! Why? |
|
December 29, 2003 |
Op-amp amplifier | An op-amp does not amplify; it just ... attenuates! An op-amp is not an amplifier; it is an ... attenuator! Why? |
|
January 05, 2004 |
Amplifier | Amplifiers do not amplify; they just ... attenuate! An amplification does not exist! It is just ... an attenuation! What do you think? Why? |
|
Paradox 32 February 28, 2005 |
Regulating element | A non-linear regulating element (e.g. a transistor acting as a current stable element) provides ... linear regulation ?!? How do we explain this paradox? |
| Interacting Voltage Sources (Potential Conflicts) | ||
|
January 12, 2004 |
Capacitive differentiator | There is something incorrect in a capacitive differentiator... What is the paradox of this popular electronic circuit? Hint: What does a voltage source "like"? What does it "hate"? |
|
November 10, 2003 |
Diode peak detector | There is something incorrect in a diode peak detector... What is the paradox of this popular electronic circuit? Hint: What does a voltage source "like"? What does it "hate"? |
|
November 17, 2003 |
Sample & hold circuit | There is something incorrect in a sample & hold circuit... What is the paradox of this popular electronic circuit? Hint: What does a voltage source "like"? What does it "hate"? |
|
November 24, 2003 |
Common-base amplifier | There is something incorrect in a common-base amplifier... What is the paradox of this popular electronic circuit? Hint: What does a voltage source "like"? What does it "hate"? |
|
December 01, 2003 |
Emitter-coupled amplifier | There is something incorrect in an emitter coupled amplifier... What is the paradox of this popular electronic circuit? Hint: What does a voltage source "like"? What does it "hate"? |
|
December 08, 2003 |
Transistor differential amplifier | There is something very incorrect in a transistor differential amplifier... What is the paradox of this popular electronic circuit? Hint: What does a voltage source "like"? What does it "hate"? |
|
Paradox 10 September 27, 2004 |
Parallel connected voltage sources (generalization) | In general, there is something very incorrect in a circuit consisting of parallel connected voltage sources... What is the paradox of this connection? Is it wrong? Is it useful? May we apply this connection into practice? |
| Interacting Current Sources (Current Conflicts) | ||
|
Paradox 11 October 04, 2004 |
Inductive differentiator | There is something incorrect in an inductive differentiator... What is the paradox of this popular electronic circuit? Hint: What does a current source "like"? What does it "hate"? |
|
Paradox 12 October 11, 2004 |
Transistor amplifier with dynamic load | There is something incorrect in a transistor amplifier with dynamic load... What is the paradox of this popular electronic circuit? Hint: What does a current source "like"? What does it "hate"? |
|
Paradox 13 October 18, 2004 |
Transistor amplifier with dynamic load controlled | There is something very incorrect in a transistor amplifier with dynamic load controlled... What is the paradox of this popular electronic circuit? Hint: What does a current source "like"? What does it "hate"? |
|
Paradox 14 October 25, 2004 |
CMOS inverter | There is something very incorrect in a CMOS inverter... What is the paradox of this popular electronic circuit? Hint: What does a current source "like"? What does it "hate"? |
|
November 01, 2004 |
Series connected current sources (generalization) | In general, there is something very incorrect in a circuit consisting of series connected current sources... What is the paradox of this connection? Is it wrong? Is it useful? May we apply this connection into practice? |
| Transistor Circuits | ||
|
Paradox 33 March 07, 2005 |
Common-base amplifier | A common-base amplifier is just a reversed common-collector amplifier (emitter follover)?!? How do we explain this paradox? | . . . |
. . . |
. . . |
Send the e-mail to cyril@circuit-fantasia.com.
Last updated March 8, 2005