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The circuit happens to be drawn connected to ground. There is no such restriction as far as I'm aware; why couldn't we float the gyrator? Oli Filth( talk| contribs) 17:21, 7 April 2010 (UTC)
Circuit dreamer: I object to the above statement reading in part "(BTW, I created it a year ago after Zen-in mutilated the Wikipedia page about negative resistance)". To refresh your memory, most of the edits on the negative resistance page were done by Spinningspark. The impetus for doing these same edits was the consensus reached that the article in question had too much WP:or and idiosyncratic POV. This was about the same time you were asked to change your username. So I did not "mutilate" this article any more than several other editors. Statements like this are unacceptable. An apology and a retraction on this discussion page is in order. Perhaps you need a wiki-break as well. Zen-in ( talk) 00:11, 8 April 2010 (UTC)
I would like to remove the note saying that gyrator-based inductor simulations can not be used in a low-pass filter, on grounds that it is probably false. It is a claim about what can not be done, which can only be taken seriously if backed by a mathematical proof whether in the article or by reference (since otherwise one at most learns that the *author* doesn't know how to do it.) Thoughts? But of course if the impossibility of using gyrator-based inductor simulators in low-pass filters has indeed been proven (which I doubt) then a better fix would be to reference that proof. Bmord ( talk) 15:55, 29 September 2010 (UTC)
I start this discussion here to demystify, once and for all, the basic idea, implementation and operation of these exotic circuits. I will use the text below as a base (I wrote it two days ago):
"Gyrator circuits imitate real elements by dynamic voltage sources with swapped instantaneous values of the voltage and the current (the voltage across the new virtual element is proportional to the current flowing through the initial real element and the current flowing through the virtual element is proportional to the voltage across the real element). These voltage sources (gyrator's outputs) are connected in opposite direction to the exciting input sources as they mimic voltage drops (in contrast, negative impedance converters with voltage inversion produce voltages). So gyrators are not only positive impedance inverters; they can "invert" in this manner any elements (linear, non-linear, time-dependent, sources, etc.) connected as a load..." Circuit dreamer ( talk) 18:20, 11 April 2010 (UTC)
The lede says "the gyrator is a positive impedance inverter" and this is true, especially in the case of a simulated inductor that converts a capacitive reactance into an inductive reactance (a capacitor into an inductor). But the problem is that impedance "impedes" the understanding gyrator circuits. What is the problem?
The problem is that impedance Z = V/I is defined as a ratio of the rms ("effective") values of the voltage and the current (see hyperphysics). Being some kind of averaged quantity, impedance hides the concepts behind all these odd circuits - gyrators, multipliers, negative impedance converters, etc. Impedance viewpoint does not allow us to realize what all these circuits actually do. As an example, you may see the result of this misleading "impedance approach" in the area of negative impedance if you browse these archived talk. Then I ( Circuit-fantasist) wasted plenty of time to show how simple the idea behind negative impedance is but I didn't manage. Now I realize why. The reason of this failure to understand one another was simple - I was thinking in terms of instantaneous values while my opponents were thinking in terms of averaged (rms) values.
The article says what a gyrator does (inverts an impedance) but it does not say how it does this magic. But the idea behind this mystic circuit is extremely simple; we will grasp it immediately if only we forget the misleading concept impedance and begin thinking in terms of instantaneous voltage and current quantities! This is the remedy - to imagine what the particular voltage and current are at each moment, to think "instantaneously":)
To understand what the particular gyrator is, it is extremely useful to understand what all related exotic circuits are. Multipliers, gyrators and negative impedance converters are used to create virtual elements that are accordingly multiplied, inverse (dual) and negative copies of actual elements. These virtual elements only mimic the original elements; they have not the same nature as the initial elements since they are implemented as dynamic voltage sources. Actual capacitors and inductors create voltage drops: a capacitor impedes the input voltage source by subtracting a voltage drop VC from the input voltage; an inductor impedes the input voltage source by creating a back emf VL and subtracting it from the input voltage. So, to simulate these behaviors, the "multiplied" and inverse virtual elements (voltage sources) are connected in opposite direction to the exciting input source to subtract a voltage drop while negative impedance converters (VNIC) are connected in the same direction to the input source to add a voltage.
A gyrator does only a simple donkeywork: it continuously "observes" the instantaneous values of the voltage across and the current through the original element (model, sample, pattern, load here...) and makes its own instantaneous output voltage proportional to the initial current and its current proportional to the initial voltage. Thus, the combination of the gyrator and the connected actual load acts as a dual 2-terminal virtual element. Shortly, a gyrator is a dynamic voltage source with swapped initial voltage and current.
You can guess that a multiplier does the same but without inversion - e.g., it makes its own output voltage equal to the initial voltage and its current proportional to the initial current. For example, a capacitance multiplier emulates an actual capacitor with an opposing dynamic voltage source (see AN-29, page 11, fig. 19 and try to guess how this clever circuit operates). Finally, you will probably realize that a negative impedance converter with voltage inversion (VNIC) is a dynamic voltage source emulating a negative resistor by adding a voltage that is equal to the voltage drop across the initial element (see this Chua's material and try to see the clever idea behind this circuit). But let's return to the gyrator.
Imagine how simple it is! The gyrator does not "know" what it converts; it is not "interested" in what an initial element is connected. The only thing that a gyrator can do is to observe the input (load's) voltage and current to produce an output (simulated) current and voltage.
Following this simple procedure, a gyrator can "invert" not only classical impedance elements (capacitors and inductors); it can invert elements of all kinds including non-linear ones. For example, a gyrator can convert a diode or a varistor (voltage-stable elements) into a transistor or a baretter (current-stable elements) and v.v. I suppose a gyrator can invert a negative impedance (negative capacitor into a negative inductance) and this extremely odd combination will have some fancy name (e.g., "injectoplactor":) It turns out a gyrator can convert almost everything. If even we put some wikipedian (e.g., Zen-in/ Circuit dreamer) at the place of the load (this is only a joke!), the gyrator will convert the poor wikipedian into his/her inversion ( Circuit dreamer/ Zen-in). It is wonderful, isn't it?
(to be continued)... Circuit dreamer ( talk) 9:20 pm, Yesterday (UTC+3)
(outdent) Right, I've made some edits to the article. I still need to update the image, but I'll get that done soon. Oli Filth( talk| contribs) 22:26, 14 April 2010 (UTC)
SpinningSpark 22:31, 14 April 2010 (UTC)
ADDED: Someone is trying to create a fake legend here. I direct people to read a copy of the ACTUAL paper from Dr. Bernard D. H. Tellegen in 1948. He did not say he actually created such a device. He said that it was conceivable (first sentence). ref: http://theeestory.com/files/article-tellegen-gyrator.pdf
Other than fancy wording in the below article there are no actual details for a new network element. Notice further, there are no pictures of this supposed "gyrator" (Telleger called it an "ideal gyrator"). The schematic referenced below shows it to be, not a new circuit element, but a circuit with resistors, inductors capacitors and an opamp. Remember that Op-amps did not exist in 1948. In the below article, the first sentence shows it was hpothetical, but the rest of the article says it is real and actually in use in POTS (plain old telephone systems) but the telephone company says they have never heard of a "gyrator". To see the real article, check the address above. You will see it was only a theoretical proposal (that never panned out). --Dan Mickle, PhD. 21MAY2012.
Hi. My point about the gyrator centers on Bernard D. H. Tellegen's description that his theoretical gyrator was a new element that would render coils/inductors and capacitors/condensers "redundant". He maintained that his gyrator was neither coil nor capacitor but a new element. This is one reason some of the description showing a "gyrator" as a resistor-capacitor network or any other sort of network using resistors, inductors or capacitors are NOT in keeping with Tellegen's description. There are several different circuits or circuit elements called or nicknamed 'gyrators', but I do not see that any of these satisfy Tellegen's proposal. There is indeed something called a gyrator used in microwave technology. It is a section of waveguide with a graphite element shaped in such a way that microwaves passing through one direction pass through normally, while in the other direction, they are delayed for a half cycle. Tellegen was not working with microwaves and I fail to see how this can apply to non-microwave signals. As to Op-amps (operational amplifiers) my real point, I believe was missed. Perhaps I did not state it clearly. The use of any circuit made up of op-amps, inductors, capacitors and resistors does not qualify as Tellegen's 5th circuit element. It is not a new element if it is made up of other already existing elements. Dr. Tellegen insisted that his new element was none of these but something totally new and different. (Please read his description to see what I mean.) What I would like to see is a drawing or patent application showing what Tellegen actually proposed.
Thank you, —Dan Mickle, PhD. — Preceding unsigned comment added by 99.18.45.0 ( talk) 08:43, 25 September 2012 (UTC)
User:Spinningspark wants a smaller archive size 17500 bytes. I think that the maximum size 17500 Byte of one archive is very small. Sawol ( talk) 07:18, 26 March 2022 (UTC)
User:Alexander Davronov, is it possible to say what is vague in the following?
Gyrators permit network realizations of two-(or-more)- port devices which cannot be realized vague with just the conventional four elements. In particular, gyrators make possible network realizations of isolators and circulators. vague
Of course it may be hard to say what is lacking when it isn't there. Taking a statement of the same form, but substituting protractor for gyrator:
Protractors permit geometric constructions which cannot be achieved vague with straightedge and compass alone. In particular, protractors make possible trisection of any given angle. vague
...is that equally vague? or is the vagueness specific to the gyrator version? catslash ( talk) 00:48, 21 June 2022 (UTC)
The gyrator article under the "Passive gyrators" heading states this: "Numerous passive circuits exist in theory for a gyrator function. However, when constructed of lumped elements there are always negative elements present." I can't seem to find such a circuit, does anyone know what this is referring to? 100.16.222.85 ( talk) 19:56, 8 May 2023 (UTC)
This
level-5 vital article is rated C-class on Wikipedia's
content assessment scale. It is of interest to the following WikiProjects: | |||||||||||
|
Archives ( Index) |
This page is archived by
ClueBot III.
|
This article links to one or more target anchors that no longer exist.
Please help fix the broken anchors. You can remove this template after fixing the problems. |
Reporting errors |
The circuit happens to be drawn connected to ground. There is no such restriction as far as I'm aware; why couldn't we float the gyrator? Oli Filth( talk| contribs) 17:21, 7 April 2010 (UTC)
Circuit dreamer: I object to the above statement reading in part "(BTW, I created it a year ago after Zen-in mutilated the Wikipedia page about negative resistance)". To refresh your memory, most of the edits on the negative resistance page were done by Spinningspark. The impetus for doing these same edits was the consensus reached that the article in question had too much WP:or and idiosyncratic POV. This was about the same time you were asked to change your username. So I did not "mutilate" this article any more than several other editors. Statements like this are unacceptable. An apology and a retraction on this discussion page is in order. Perhaps you need a wiki-break as well. Zen-in ( talk) 00:11, 8 April 2010 (UTC)
I would like to remove the note saying that gyrator-based inductor simulations can not be used in a low-pass filter, on grounds that it is probably false. It is a claim about what can not be done, which can only be taken seriously if backed by a mathematical proof whether in the article or by reference (since otherwise one at most learns that the *author* doesn't know how to do it.) Thoughts? But of course if the impossibility of using gyrator-based inductor simulators in low-pass filters has indeed been proven (which I doubt) then a better fix would be to reference that proof. Bmord ( talk) 15:55, 29 September 2010 (UTC)
I start this discussion here to demystify, once and for all, the basic idea, implementation and operation of these exotic circuits. I will use the text below as a base (I wrote it two days ago):
"Gyrator circuits imitate real elements by dynamic voltage sources with swapped instantaneous values of the voltage and the current (the voltage across the new virtual element is proportional to the current flowing through the initial real element and the current flowing through the virtual element is proportional to the voltage across the real element). These voltage sources (gyrator's outputs) are connected in opposite direction to the exciting input sources as they mimic voltage drops (in contrast, negative impedance converters with voltage inversion produce voltages). So gyrators are not only positive impedance inverters; they can "invert" in this manner any elements (linear, non-linear, time-dependent, sources, etc.) connected as a load..." Circuit dreamer ( talk) 18:20, 11 April 2010 (UTC)
The lede says "the gyrator is a positive impedance inverter" and this is true, especially in the case of a simulated inductor that converts a capacitive reactance into an inductive reactance (a capacitor into an inductor). But the problem is that impedance "impedes" the understanding gyrator circuits. What is the problem?
The problem is that impedance Z = V/I is defined as a ratio of the rms ("effective") values of the voltage and the current (see hyperphysics). Being some kind of averaged quantity, impedance hides the concepts behind all these odd circuits - gyrators, multipliers, negative impedance converters, etc. Impedance viewpoint does not allow us to realize what all these circuits actually do. As an example, you may see the result of this misleading "impedance approach" in the area of negative impedance if you browse these archived talk. Then I ( Circuit-fantasist) wasted plenty of time to show how simple the idea behind negative impedance is but I didn't manage. Now I realize why. The reason of this failure to understand one another was simple - I was thinking in terms of instantaneous values while my opponents were thinking in terms of averaged (rms) values.
The article says what a gyrator does (inverts an impedance) but it does not say how it does this magic. But the idea behind this mystic circuit is extremely simple; we will grasp it immediately if only we forget the misleading concept impedance and begin thinking in terms of instantaneous voltage and current quantities! This is the remedy - to imagine what the particular voltage and current are at each moment, to think "instantaneously":)
To understand what the particular gyrator is, it is extremely useful to understand what all related exotic circuits are. Multipliers, gyrators and negative impedance converters are used to create virtual elements that are accordingly multiplied, inverse (dual) and negative copies of actual elements. These virtual elements only mimic the original elements; they have not the same nature as the initial elements since they are implemented as dynamic voltage sources. Actual capacitors and inductors create voltage drops: a capacitor impedes the input voltage source by subtracting a voltage drop VC from the input voltage; an inductor impedes the input voltage source by creating a back emf VL and subtracting it from the input voltage. So, to simulate these behaviors, the "multiplied" and inverse virtual elements (voltage sources) are connected in opposite direction to the exciting input source to subtract a voltage drop while negative impedance converters (VNIC) are connected in the same direction to the input source to add a voltage.
A gyrator does only a simple donkeywork: it continuously "observes" the instantaneous values of the voltage across and the current through the original element (model, sample, pattern, load here...) and makes its own instantaneous output voltage proportional to the initial current and its current proportional to the initial voltage. Thus, the combination of the gyrator and the connected actual load acts as a dual 2-terminal virtual element. Shortly, a gyrator is a dynamic voltage source with swapped initial voltage and current.
You can guess that a multiplier does the same but without inversion - e.g., it makes its own output voltage equal to the initial voltage and its current proportional to the initial current. For example, a capacitance multiplier emulates an actual capacitor with an opposing dynamic voltage source (see AN-29, page 11, fig. 19 and try to guess how this clever circuit operates). Finally, you will probably realize that a negative impedance converter with voltage inversion (VNIC) is a dynamic voltage source emulating a negative resistor by adding a voltage that is equal to the voltage drop across the initial element (see this Chua's material and try to see the clever idea behind this circuit). But let's return to the gyrator.
Imagine how simple it is! The gyrator does not "know" what it converts; it is not "interested" in what an initial element is connected. The only thing that a gyrator can do is to observe the input (load's) voltage and current to produce an output (simulated) current and voltage.
Following this simple procedure, a gyrator can "invert" not only classical impedance elements (capacitors and inductors); it can invert elements of all kinds including non-linear ones. For example, a gyrator can convert a diode or a varistor (voltage-stable elements) into a transistor or a baretter (current-stable elements) and v.v. I suppose a gyrator can invert a negative impedance (negative capacitor into a negative inductance) and this extremely odd combination will have some fancy name (e.g., "injectoplactor":) It turns out a gyrator can convert almost everything. If even we put some wikipedian (e.g., Zen-in/ Circuit dreamer) at the place of the load (this is only a joke!), the gyrator will convert the poor wikipedian into his/her inversion ( Circuit dreamer/ Zen-in). It is wonderful, isn't it?
(to be continued)... Circuit dreamer ( talk) 9:20 pm, Yesterday (UTC+3)
(outdent) Right, I've made some edits to the article. I still need to update the image, but I'll get that done soon. Oli Filth( talk| contribs) 22:26, 14 April 2010 (UTC)
SpinningSpark 22:31, 14 April 2010 (UTC)
ADDED: Someone is trying to create a fake legend here. I direct people to read a copy of the ACTUAL paper from Dr. Bernard D. H. Tellegen in 1948. He did not say he actually created such a device. He said that it was conceivable (first sentence). ref: http://theeestory.com/files/article-tellegen-gyrator.pdf
Other than fancy wording in the below article there are no actual details for a new network element. Notice further, there are no pictures of this supposed "gyrator" (Telleger called it an "ideal gyrator"). The schematic referenced below shows it to be, not a new circuit element, but a circuit with resistors, inductors capacitors and an opamp. Remember that Op-amps did not exist in 1948. In the below article, the first sentence shows it was hpothetical, but the rest of the article says it is real and actually in use in POTS (plain old telephone systems) but the telephone company says they have never heard of a "gyrator". To see the real article, check the address above. You will see it was only a theoretical proposal (that never panned out). --Dan Mickle, PhD. 21MAY2012.
Hi. My point about the gyrator centers on Bernard D. H. Tellegen's description that his theoretical gyrator was a new element that would render coils/inductors and capacitors/condensers "redundant". He maintained that his gyrator was neither coil nor capacitor but a new element. This is one reason some of the description showing a "gyrator" as a resistor-capacitor network or any other sort of network using resistors, inductors or capacitors are NOT in keeping with Tellegen's description. There are several different circuits or circuit elements called or nicknamed 'gyrators', but I do not see that any of these satisfy Tellegen's proposal. There is indeed something called a gyrator used in microwave technology. It is a section of waveguide with a graphite element shaped in such a way that microwaves passing through one direction pass through normally, while in the other direction, they are delayed for a half cycle. Tellegen was not working with microwaves and I fail to see how this can apply to non-microwave signals. As to Op-amps (operational amplifiers) my real point, I believe was missed. Perhaps I did not state it clearly. The use of any circuit made up of op-amps, inductors, capacitors and resistors does not qualify as Tellegen's 5th circuit element. It is not a new element if it is made up of other already existing elements. Dr. Tellegen insisted that his new element was none of these but something totally new and different. (Please read his description to see what I mean.) What I would like to see is a drawing or patent application showing what Tellegen actually proposed.
Thank you, —Dan Mickle, PhD. — Preceding unsigned comment added by 99.18.45.0 ( talk) 08:43, 25 September 2012 (UTC)
User:Spinningspark wants a smaller archive size 17500 bytes. I think that the maximum size 17500 Byte of one archive is very small. Sawol ( talk) 07:18, 26 March 2022 (UTC)
User:Alexander Davronov, is it possible to say what is vague in the following?
Gyrators permit network realizations of two-(or-more)- port devices which cannot be realized vague with just the conventional four elements. In particular, gyrators make possible network realizations of isolators and circulators. vague
Of course it may be hard to say what is lacking when it isn't there. Taking a statement of the same form, but substituting protractor for gyrator:
Protractors permit geometric constructions which cannot be achieved vague with straightedge and compass alone. In particular, protractors make possible trisection of any given angle. vague
...is that equally vague? or is the vagueness specific to the gyrator version? catslash ( talk) 00:48, 21 June 2022 (UTC)
The gyrator article under the "Passive gyrators" heading states this: "Numerous passive circuits exist in theory for a gyrator function. However, when constructed of lumped elements there are always negative elements present." I can't seem to find such a circuit, does anyone know what this is referring to? 100.16.222.85 ( talk) 19:56, 8 May 2023 (UTC)