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Air gap increases reluctance, so less B-field occurs per applied H-field. And since the stored energy is measured by volume integral of product of H and B-fields, stored energy will tend to decrease as the air gap increases.
An expert of this topic should revise this statement and remove it if necessary.
AhmedHan ( talk) 06:03, 2 May 2014 (UTC)
You can apply more H-field, as the core will require more H to saturate. So more air gap leads to more energy storage capability (although you should resize windings to the new higher current)
Strictly, the flyback transformer converts the deflection power supply voltage, not the "mains" ( input AC) voltage, to high voltage. Is this worth distinguishing in the text, without turning this into an article on TV repair? -- Wtshymanski 05:24, 20 Apr 2005 (UTC)
I thought it was desirable for all transformers to have high inductance windings (not just flybacks) in order to extend LF response and cut down the magnetising current. Am I wrong? Does the author intend to say good coupling or low leakage inductance? Light current 16:48, 31 August 2005 (UTC)
Wtshymanski & Light current have good points. The deflection power supply is typically on the order of 70vdc and it is not correct to claim line voltage (AC) as the input to the LOPT. Additionally the inductance of mains (50/60Hz) transformers must be made high in order to reduce the magnetising current to acceptable levels and also to prevent saturation (applies to audio as well). On leakage inductance, it would be highly undesirable to have high leakage inductance in a LOPT as leakage inductance represents stored energy that has to be adsorbed by snubber circuits. In the case of mains transformers, if the output is driving a capacitive load (eg the voltage multiplier in a microwave oven) a high leakage inductance would be desirable in order to zero the power factor. I am not an audio expert, but I would imagine that the leakage inductance of an audio transformer would be quite low to insure minimal parasitic inductance in the circuit. It should also be made clear that the LOPT and associated circuitry is operated as a switched mode power supply and outputs a square voltage waveform given that the circuit switches between positive, constant di/dt and negative, constant di/dt. Additionally the voltage multiplier is not distinct from the "rectifier" as a CW multiplier intrinsically has a DC output. The author of the claims that the LOPT is responsible for the wine of monitors - this cannot be correct as all monitors operate with horizontal scans in excess of 40kHz - well above the range of human hearing. A much more likely source of audible sound is the mains stepdown transformer which may operate within the range of human hearing.
This article seems to be about a particular application of flyback transformers (CRTs). The discussion of the electrical componant gets lost in the discussion about a particular application. There are other uses of flyback transformers, and I think that the detailed CRT discussion should have its own page. —Preceding unsigned comment added by 206.197.156.11 ( talk) 12:57, 27 March 2009 (UTC)
"The primary winding of the LOPT is driven by a relatively low voltage sawtooth wave ..."
No it isn't. The input current to the primary winding is a switch (usually a transistor these days) which is either on (short circuit) or off (open circuit). The input to the transistor is not saw tooth in any shape or form, it is a switching pulse. The output from the transistor would not ba sawtooth either were it not for the inductance of the primary of the transformer. When the switch switches on, current starts to build up in the primary increasing from zero to its maximum courtesy of the inductance. When the switch switches off, the current has to collapse to zero very quickly. Thus the current in the primary, and hence the secondary is sawtooth (however, the voltage certainly isn't). As the current collapses, there is considerable energy stored in the magnetic core. It is this energy that is exploited, and is coupled out using suitable secondary windings and a simple half wave recifier to provide the basis of a power supply.
The article requires a complete rewrite, to correct the many errors and to make it application non specific. I would do it, but I don't presently have the time. 86.163.86.161 ( talk) 17:12, 24 February 2011 (UTC)
A user placed the floowing in the article, at has been removed "A better description is on flyback converter. This whole article is merely about the application in the TV, the only place where it is synchronized with the flyback of an electron beam, even computer monitors do not do it this way." Since the Flyback system is specific to television and related techniques, I don't think the comment is valid, but wanted to preserve it just so it is not acted on. cmacd 19:30, 16 February 2007 (UTC)
Before the flyback (1940s) - Tv sets sometimes used an RF power supply for the High voltage, which could be lethal. The flyback system will be loaded so much that it does not normaly kill. cmacd 19:32, 16 February 2007 (UTC)
"Flyback transformers are a frequent source of TV tube failure."
I can't imagine how this could occur. CRTs are pretty robust things, like most thermionic devices, and I cant imagine any real world LOPT failure putting damagingly high V or i onto the tube. Tabby ( talk) 23:26, 25 November 2007 (UTC)
A "flyback transformer" by definition is not, in fact, a high-voltage transformer, nor is it even a step-up transformer. This article, while thorough, useful, and generally well-written, is a very limited definition. It belongs more as a discussion topic in a broader article than as the entire definition.
A flyback transformer is actually a coupled inductor used in a DC/DC converter. All energy transferred to the secondary is stored in the transformer core by the primary winding during one part of the cycle and released through the secondary winding during the other part. This differs from a traditional transformer, where flux generated the by the voltage-seconds on the primary is opposed simultaneously by the flux generated by the volt-seconds on the secondary. The core in a traditional transformer merely facilitates coupling between the windings but does not store the energy being transferred.
A flyback converter as used in a television is a special case of this topology. It generates high voltage and does all of the things described in this article.
The following article more accurately explains the meaning of the term "flyback transformer": http://en.wikipedia.org/wiki/Flyback_converter —Preceding unsigned comment added by Molain ( talk • contribs) 02:01, 26 January 2010 (UTC)
how do i change a flyback transformer —Preceding unsigned comment added by Rcaman ( talk • contribs) 01:24, 15 March 2010 (UTC)
The sole original purpose of the device was to produce the high deflection currents required for the CRT. In original (like 1930's) TV sets, the high voltage for the CRT was not derived from the line output transformer (aka flyback transformer). It was derived from a winding on the mains transformer that these early sets were equipped with. Apart from being downright lethal, this method was a considerable fire risk due the poor insulating materials then available.
The task of generating the high voltage was moved to the line output transformer, when mains transformers were no longer used when the AC/DC design was adopted. Although modern usage of these transformers no longer generates the high voltage required for CRTs, there are several designs that produce high voltages for other purposes (e.g. particle accelrators). It is therefore not correct to say that these devices no longer produce high voltages, but it is correct to state that they no longer produce large currents (for deflection purposes where they were produced at practically zero voltage). 86.163.87.193 ( talk) 16:49, 30 July 2011 (UTC)
This article is still very much based on guesswork and supposition. It is far from accurate as shown by the above discussion. Areas of concern include (but are not limited to):
Most (but not all) of these points not necessarily relevant to a purely flyback type power supply DieSwartzPunkt ( talk) 15:41, 10 November 2012 (UTC)
Most of the electrical components pages could use a bit of tidying up, but...
Out of all the different articles of this sort, the expected quality of this page is much lower than the actual quality.
It's obviously lower rank than resistors and capacitors and the like, but it's still far from an obscure component. Considering the noteworthiness of the topic of this article, it really ought to get a bit of dedicated attention one of these days (imho)
50.46.228.138 ( talk) 23:02, 10 January 2014 (UTC)
This article is empty. I can see there is discussion about this though. There are no schematics or diagrams, no numbers or units, and seemingly no facts. Half the article goes off into television repair, which does not even apply to the main article. — Preceding unsigned comment added by 99.229.12.128 ( talk) 23:31, 17 March 2016 (UTC)
It doesn't even explain why the transformer is called a "flyback". You keep reading and reading and it's still a mystery.
I found this Stack Exchange post somewhat useful: http://electronics.stackexchange.com/questions/235991/what-is-a-flyback
A5 ( talk) 02:51, 31 May 2016 (UTC)
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Air gap increases reluctance, so less B-field occurs per applied H-field. And since the stored energy is measured by volume integral of product of H and B-fields, stored energy will tend to decrease as the air gap increases.
An expert of this topic should revise this statement and remove it if necessary.
AhmedHan ( talk) 06:03, 2 May 2014 (UTC)
You can apply more H-field, as the core will require more H to saturate. So more air gap leads to more energy storage capability (although you should resize windings to the new higher current)
Strictly, the flyback transformer converts the deflection power supply voltage, not the "mains" ( input AC) voltage, to high voltage. Is this worth distinguishing in the text, without turning this into an article on TV repair? -- Wtshymanski 05:24, 20 Apr 2005 (UTC)
I thought it was desirable for all transformers to have high inductance windings (not just flybacks) in order to extend LF response and cut down the magnetising current. Am I wrong? Does the author intend to say good coupling or low leakage inductance? Light current 16:48, 31 August 2005 (UTC)
Wtshymanski & Light current have good points. The deflection power supply is typically on the order of 70vdc and it is not correct to claim line voltage (AC) as the input to the LOPT. Additionally the inductance of mains (50/60Hz) transformers must be made high in order to reduce the magnetising current to acceptable levels and also to prevent saturation (applies to audio as well). On leakage inductance, it would be highly undesirable to have high leakage inductance in a LOPT as leakage inductance represents stored energy that has to be adsorbed by snubber circuits. In the case of mains transformers, if the output is driving a capacitive load (eg the voltage multiplier in a microwave oven) a high leakage inductance would be desirable in order to zero the power factor. I am not an audio expert, but I would imagine that the leakage inductance of an audio transformer would be quite low to insure minimal parasitic inductance in the circuit. It should also be made clear that the LOPT and associated circuitry is operated as a switched mode power supply and outputs a square voltage waveform given that the circuit switches between positive, constant di/dt and negative, constant di/dt. Additionally the voltage multiplier is not distinct from the "rectifier" as a CW multiplier intrinsically has a DC output. The author of the claims that the LOPT is responsible for the wine of monitors - this cannot be correct as all monitors operate with horizontal scans in excess of 40kHz - well above the range of human hearing. A much more likely source of audible sound is the mains stepdown transformer which may operate within the range of human hearing.
This article seems to be about a particular application of flyback transformers (CRTs). The discussion of the electrical componant gets lost in the discussion about a particular application. There are other uses of flyback transformers, and I think that the detailed CRT discussion should have its own page. —Preceding unsigned comment added by 206.197.156.11 ( talk) 12:57, 27 March 2009 (UTC)
"The primary winding of the LOPT is driven by a relatively low voltage sawtooth wave ..."
No it isn't. The input current to the primary winding is a switch (usually a transistor these days) which is either on (short circuit) or off (open circuit). The input to the transistor is not saw tooth in any shape or form, it is a switching pulse. The output from the transistor would not ba sawtooth either were it not for the inductance of the primary of the transformer. When the switch switches on, current starts to build up in the primary increasing from zero to its maximum courtesy of the inductance. When the switch switches off, the current has to collapse to zero very quickly. Thus the current in the primary, and hence the secondary is sawtooth (however, the voltage certainly isn't). As the current collapses, there is considerable energy stored in the magnetic core. It is this energy that is exploited, and is coupled out using suitable secondary windings and a simple half wave recifier to provide the basis of a power supply.
The article requires a complete rewrite, to correct the many errors and to make it application non specific. I would do it, but I don't presently have the time. 86.163.86.161 ( talk) 17:12, 24 February 2011 (UTC)
A user placed the floowing in the article, at has been removed "A better description is on flyback converter. This whole article is merely about the application in the TV, the only place where it is synchronized with the flyback of an electron beam, even computer monitors do not do it this way." Since the Flyback system is specific to television and related techniques, I don't think the comment is valid, but wanted to preserve it just so it is not acted on. cmacd 19:30, 16 February 2007 (UTC)
Before the flyback (1940s) - Tv sets sometimes used an RF power supply for the High voltage, which could be lethal. The flyback system will be loaded so much that it does not normaly kill. cmacd 19:32, 16 February 2007 (UTC)
"Flyback transformers are a frequent source of TV tube failure."
I can't imagine how this could occur. CRTs are pretty robust things, like most thermionic devices, and I cant imagine any real world LOPT failure putting damagingly high V or i onto the tube. Tabby ( talk) 23:26, 25 November 2007 (UTC)
A "flyback transformer" by definition is not, in fact, a high-voltage transformer, nor is it even a step-up transformer. This article, while thorough, useful, and generally well-written, is a very limited definition. It belongs more as a discussion topic in a broader article than as the entire definition.
A flyback transformer is actually a coupled inductor used in a DC/DC converter. All energy transferred to the secondary is stored in the transformer core by the primary winding during one part of the cycle and released through the secondary winding during the other part. This differs from a traditional transformer, where flux generated the by the voltage-seconds on the primary is opposed simultaneously by the flux generated by the volt-seconds on the secondary. The core in a traditional transformer merely facilitates coupling between the windings but does not store the energy being transferred.
A flyback converter as used in a television is a special case of this topology. It generates high voltage and does all of the things described in this article.
The following article more accurately explains the meaning of the term "flyback transformer": http://en.wikipedia.org/wiki/Flyback_converter —Preceding unsigned comment added by Molain ( talk • contribs) 02:01, 26 January 2010 (UTC)
how do i change a flyback transformer —Preceding unsigned comment added by Rcaman ( talk • contribs) 01:24, 15 March 2010 (UTC)
The sole original purpose of the device was to produce the high deflection currents required for the CRT. In original (like 1930's) TV sets, the high voltage for the CRT was not derived from the line output transformer (aka flyback transformer). It was derived from a winding on the mains transformer that these early sets were equipped with. Apart from being downright lethal, this method was a considerable fire risk due the poor insulating materials then available.
The task of generating the high voltage was moved to the line output transformer, when mains transformers were no longer used when the AC/DC design was adopted. Although modern usage of these transformers no longer generates the high voltage required for CRTs, there are several designs that produce high voltages for other purposes (e.g. particle accelrators). It is therefore not correct to say that these devices no longer produce high voltages, but it is correct to state that they no longer produce large currents (for deflection purposes where they were produced at practically zero voltage). 86.163.87.193 ( talk) 16:49, 30 July 2011 (UTC)
This article is still very much based on guesswork and supposition. It is far from accurate as shown by the above discussion. Areas of concern include (but are not limited to):
Most (but not all) of these points not necessarily relevant to a purely flyback type power supply DieSwartzPunkt ( talk) 15:41, 10 November 2012 (UTC)
Most of the electrical components pages could use a bit of tidying up, but...
Out of all the different articles of this sort, the expected quality of this page is much lower than the actual quality.
It's obviously lower rank than resistors and capacitors and the like, but it's still far from an obscure component. Considering the noteworthiness of the topic of this article, it really ought to get a bit of dedicated attention one of these days (imho)
50.46.228.138 ( talk) 23:02, 10 January 2014 (UTC)
This article is empty. I can see there is discussion about this though. There are no schematics or diagrams, no numbers or units, and seemingly no facts. Half the article goes off into television repair, which does not even apply to the main article. — Preceding unsigned comment added by 99.229.12.128 ( talk) 23:31, 17 March 2016 (UTC)
It doesn't even explain why the transformer is called a "flyback". You keep reading and reading and it's still a mystery.
I found this Stack Exchange post somewhat useful: http://electronics.stackexchange.com/questions/235991/what-is-a-flyback
A5 ( talk) 02:51, 31 May 2016 (UTC)