This document describes a new mode of operation for pentode or tetrode power tubes in audio power amplifiers. It involves using back-to-back connected diodes to alternately connect the screen grids of the power tubes to different taps on the output transformer plate winding. This causes the power tubes to operate under different characteristics depending on the polarity of the grid signal voltage. This allows the power tubes to avoid operating in cutoff regions, preventing notch distortion while maintaining high efficiency. The design provides advantages over conventional amplifier designs like higher power output with lower distortion and components costs.
This document describes transistor mixing circuits for combining two electric oscillations. It discloses a circuit using a transistor with at least one emitter electrode, two base electrodes, and a collector electrode. A first source of oscillations is connected between the emitter and one or both base electrodes. A second source is coupled to an input circuit including one of the base electrodes. The circuit proportions ensure the sources are decoupled from each other's oscillations, while the modulation products pass through. Figures 1-4 illustrate example circuits including a push-pull modulator and point-contact transistor configurations. Characteristics are also shown to explain the circuit operation.
This document discusses different classes of power amplifiers including class A, B, AB, and C. Class A amplifiers have an output transistor biased to conduct over the entire input cycle but have low maximum efficiency of 25%. Class B amplifiers use two complementary transistors that each conduct for half of the input cycle, improving maximum efficiency to 50% but introducing crossover distortion. Class AB amplifiers operate the transistors slightly more than half of each cycle to reduce crossover distortion. Inductive and transformer coupling can further improve the maximum efficiency of class A and B amplifiers.
A New Filtering Method and a Novel Converter Transformer for HVDC System.IOSR Journals
This document presents a new filtering method and converter transformer design for HVDC systems. The new design aims to address issues with traditional converter transformers and passive filtering methods, such as additional harmonic losses and difficulties meeting insulation requirements.
The new converter transformer uses a prolonged-delta winding configuration and phase shifts of 15 degrees to provide 12-phase commutation voltages. It also employs an inductive filtering mechanism where a tap connects the prolonged and common windings to an LC resonance circuit. This allows harmonic currents to balance out so no inductive harmonics flow in the primary winding.
Simulation results show the new design greatly reduces harmonic content and transformer losses compared to traditional designs. The primary current waveform has lower distortion and THD with the
This document describes a patent for improvements to electronic time-base generators. It includes a circuit diagram and description of a generator that uses negative feedback to linearize the output waveform by differentiating the voltage across a scanning coil and using it to control a feedback valve. This counteracts nonlinearity from exponential charging/discharging of capacitors. It allows the scanning speed and sweep magnitude to be varied by controlling the bias on the feedback valve.
This document describes a patent for improvements to electronic time-base generators. It includes a circuit diagram and description of a generator that uses negative feedback to linearize the output waveform by differentiating the voltage across a scanning coil and using it to control a feedback valve. This counteracts nonlinearity from exponential charging/discharging of capacitors. It allows the scanning speed and sweep magnitude to be continuously variable via a bias control on the feedback valve.
International Journal of Engineering Research and Applications (IJERA) aims to cover the latest outstanding developments in the field of all Engineering Technologies & science.
International Journal of Engineering Research and Applications (IJERA) is a team of researchers not publication services or private publications running the journals for monetary benefits, we are association of scientists and academia who focus only on supporting authors who want to publish their work. The articles published in our journal can be accessed online, all the articles will be archived for real time access.
Our journal system primarily aims to bring out the research talent and the works done by sciaentists, academia, engineers, practitioners, scholars, post graduate students of engineering and science. This journal aims to cover the scientific research in a broader sense and not publishing a niche area of research facilitating researchers from various verticals to publish their papers. It is also aimed to provide a platform for the researchers to publish in a shorter of time, enabling them to continue further All articles published are freely available to scientific researchers in the Government agencies,educators and the general public. We are taking serious efforts to promote our journal across the globe in various ways, we are sure that our journal will act as a scientific platform for all researchers to publish their works online.
This document provides an overview of waveform generators and special function integrated circuits. It discusses various waveform generator circuits like sine wave generators using RC phase shift oscillators and Wien bridge oscillators. It also discusses multivibrators circuits like astable and monostable multivibrators that can generate square waves. In addition, it covers the 555 timer IC which can be used in monostable and astable configurations to generate pulses, and function generator ICs like the ICL8038 that can produce sine, square and triangular waves.
This document describes transistor mixing circuits for combining two electric oscillations. It discloses a circuit using a transistor with at least one emitter electrode, two base electrodes, and a collector electrode. A first source of oscillations is connected between the emitter and one or both base electrodes. A second source is coupled to an input circuit including one of the base electrodes. The circuit proportions ensure the sources are decoupled from each other's oscillations, while the modulation products pass through. Figures 1-4 illustrate example circuits including a push-pull modulator and point-contact transistor configurations. Characteristics are also shown to explain the circuit operation.
This document discusses different classes of power amplifiers including class A, B, AB, and C. Class A amplifiers have an output transistor biased to conduct over the entire input cycle but have low maximum efficiency of 25%. Class B amplifiers use two complementary transistors that each conduct for half of the input cycle, improving maximum efficiency to 50% but introducing crossover distortion. Class AB amplifiers operate the transistors slightly more than half of each cycle to reduce crossover distortion. Inductive and transformer coupling can further improve the maximum efficiency of class A and B amplifiers.
A New Filtering Method and a Novel Converter Transformer for HVDC System.IOSR Journals
This document presents a new filtering method and converter transformer design for HVDC systems. The new design aims to address issues with traditional converter transformers and passive filtering methods, such as additional harmonic losses and difficulties meeting insulation requirements.
The new converter transformer uses a prolonged-delta winding configuration and phase shifts of 15 degrees to provide 12-phase commutation voltages. It also employs an inductive filtering mechanism where a tap connects the prolonged and common windings to an LC resonance circuit. This allows harmonic currents to balance out so no inductive harmonics flow in the primary winding.
Simulation results show the new design greatly reduces harmonic content and transformer losses compared to traditional designs. The primary current waveform has lower distortion and THD with the
This document describes a patent for improvements to electronic time-base generators. It includes a circuit diagram and description of a generator that uses negative feedback to linearize the output waveform by differentiating the voltage across a scanning coil and using it to control a feedback valve. This counteracts nonlinearity from exponential charging/discharging of capacitors. It allows the scanning speed and sweep magnitude to be varied by controlling the bias on the feedback valve.
This document describes a patent for improvements to electronic time-base generators. It includes a circuit diagram and description of a generator that uses negative feedback to linearize the output waveform by differentiating the voltage across a scanning coil and using it to control a feedback valve. This counteracts nonlinearity from exponential charging/discharging of capacitors. It allows the scanning speed and sweep magnitude to be continuously variable via a bias control on the feedback valve.
International Journal of Engineering Research and Applications (IJERA) aims to cover the latest outstanding developments in the field of all Engineering Technologies & science.
International Journal of Engineering Research and Applications (IJERA) is a team of researchers not publication services or private publications running the journals for monetary benefits, we are association of scientists and academia who focus only on supporting authors who want to publish their work. The articles published in our journal can be accessed online, all the articles will be archived for real time access.
Our journal system primarily aims to bring out the research talent and the works done by sciaentists, academia, engineers, practitioners, scholars, post graduate students of engineering and science. This journal aims to cover the scientific research in a broader sense and not publishing a niche area of research facilitating researchers from various verticals to publish their papers. It is also aimed to provide a platform for the researchers to publish in a shorter of time, enabling them to continue further All articles published are freely available to scientific researchers in the Government agencies,educators and the general public. We are taking serious efforts to promote our journal across the globe in various ways, we are sure that our journal will act as a scientific platform for all researchers to publish their works online.
This document provides an overview of waveform generators and special function integrated circuits. It discusses various waveform generator circuits like sine wave generators using RC phase shift oscillators and Wien bridge oscillators. It also discusses multivibrators circuits like astable and monostable multivibrators that can generate square waves. In addition, it covers the 555 timer IC which can be used in monostable and astable configurations to generate pulses, and function generator ICs like the ICL8038 that can produce sine, square and triangular waves.
Simulation of SPWM based Z-Source InverterIOSR Journals
1) The document presents a simulation of a SPWM based Z-source inverter. Z-source inverters can boost or buck the output voltage from a DC supply, overcoming limitations of traditional voltage source inverters.
2) MATLAB/Simulink models were developed for a Z-source inverter feeding resistive, inductive, and motor loads. Simulation results validated that the Z-source inverter has lower total harmonic distortion than traditional voltage source and current source inverters.
3) The Z-source inverter topology was analyzed and its operating principle explained. Sinusoidal pulse width modulation was used for switching control. Simulation results showed improved performance of the Z-source inverter over
Pre Final Year project/ mini project for Electronics and communication engine...Shirshendu Das
The document describes a project to construct a full wave rectifier circuit that converts 220V AC input into 5V, -5V, and variable 5V DC output. It includes a center tapped transformer, bridge rectifier using 4 diodes, and voltage regulators. Capacitor filters are used to obtain smooth DC waveforms from the pulsating rectified output. The circuit is simulated using NI Multisim software and experimental results are analyzed. Positive 5V output is obtained using an LM7805 regulator, negative 5V output uses an LM7905 regulator, and an LM317 provides adjustable output.
IRJET- Design and Implementation of Isolated Multi-Output Flyback ConverterIRJET Journal
This document describes the design and implementation of an isolated multi-output flyback converter. A flyback converter uses a single switch and transformer to provide isolated output voltages from an input source. The designed converter uses a toroidal transformer with multiple secondary windings to generate multiple isolated output voltages at fixed levels. Simulation results and specifications for the transformer, switch, and outputs are provided. The flyback converter provides an efficient and low-cost solution for applications requiring multiple isolated low-power DC outputs.
This document discusses power semiconductor devices, including:
1) It provides an overview of common power semiconductor devices like diodes, bipolar transistors, thyristors, MOSFETs, and IGBTs and discusses their typical power and frequency ranges.
2) It describes the construction and operation of p-n junction diodes, including their reverse recovery characteristics and how minority carrier lifetime affects on-state voltage and turn-off losses.
3) It discusses the reverse bias behavior of p-n junction diodes and how the peak electric field is related to the avalanche voltage and reverse leakage current.
A Plasma Tweeter is an audio device which uses a pair of electrodes as a source of sound. It has a clear reproduction and Omni directional radiation pattern. A plasma tweeter has a better frequency response than a conventional speaker and does not involve any moving part (diaphragm) and thus has less reverberation and no wear and tear. Plasma tweeters invented earlier were very expensive. This paper presents a plasma audio system which is making the regular audio system more efficient because of the use of the latest plasma tweeter. Here the objective is to create a low cost and more efficient version of the most speakers invented till now with the complete audio system.
1) Power bipolar junction transistors and Darlington transistors are high power versions of conventional transistors used as static switches in power electronics. They have current ratings of several hundred amps and voltage ratings of several hundred volts.
2) Darlington transistors have a higher gain than single transistors, alleviating the need for high base drive currents.
3) Proper operation requires that transistors remain in saturation to avoid high power dissipation, and within safe operating areas defined by maximum voltage, current, and power boundaries.
1. Power bipolar junction transistors and Darlington transistors are high power versions of conventional transistors used as static switches in power electronics. They have current ratings of several hundred amps and voltage ratings of several hundred volts.
2. Darlington transistors have a higher gain than single transistors and are used when higher base currents are needed to adequately turn on the transistor.
3. The safe operating area of a transistor specifies boundaries on its current and voltage ratings to ensure safe operation without damage. Exceeding these boundaries can lead to avalanche breakdown or second breakdown failure mechanisms.
This document analyzes a transistor clamped H-bridge split phase PWM inverter. It presents the circuit diagram of the proposed inverter which uses coupled inductors to prevent short circuits and reduce reverse recovery losses. A double reference single carrier modulation technique is used to generate PWM signals from two reference signals and a triangular carrier, producing a five-level output voltage. Simulation results in MATLAB Simulink show the five-level output voltage waveform and total harmonic distortion of 8.43%, demonstrating reduced harmonics compared to conventional inverters. The proposed inverter topology and modulation control method aim to improve efficiency, reliability and output waveform quality.
The document summarizes different classes of amplifiers, including power amplifiers, class A amplifiers, and class B amplifiers. It describes the main function of power amplifiers as delivering power to the load. It then discusses the single-ended class A amplifier circuit and its low efficiency of less than 30%. Finally, it introduces the class B push-pull amplifier circuit which uses two complementary transistors to conduct alternating half cycles, improving efficiency to around 70%.
Infomatica, as it stands today, is a manifestation of our values, toil, and dedication towards imparting knowledge to the pupils of the society. Visit us: http://www.infomaticaacademy.com/
This document contains questions and answers related to power electronics topics like phase controlled converters. Some key points:
- Phase controlled rectifiers convert fixed AC voltage to variable DC voltage by controlling the firing delay angle. Common applications include motor drives, traction systems, and process control.
- Freewheeling diodes improve input power factor and output current waveform quality in controlled rectifiers.
- Single phase bridge converters have advantages over midpoint converters like lower peak inverse voltages on SCRs and lower transformer ratings.
- Firing circuits for line commutated converters include UJT, cosine wave crossing pulse timing control, and digital schemes.
- Six-pulse converters have simpler commutation and reduced lower order
This document describes improvements to cyanine dyestuffs, specifically those useful for sensitizing photographic silver halide emulsions. The cyanine dyestuffs are obtained by reacting a terazole quaternary salt with a 5 or 6-membered heterocyclic nitrogen compound or a heterocyclic nitrogen ketomethylene nucleus. The resulting products have general formulas IV or V, representing cyanine dyes that may exist in different resonance forms. The dyes described contain substituents like alkyl, cycloalkyl, aryl, and heterocyclic groups.
This document contains questions and answers related to power electronics devices and converters. It begins with definitions of key power electronics terms:
- IGBT is popular due to lower switching losses and smaller snubber circuit requirements.
- Thyristors can be turned on through forward voltage, gate, dv/dt, temperature, or light triggering.
- Power diodes have higher voltage, current, and power ratings than signal diodes due to a drift region construction.
- IGBTs, power MOSFETs, and power BJTs are voltage, voltage, and current controlled devices respectively due to how their output current is controlled by their input signals.
- There are N-channel and P-channel
Hardware Analysis of Resonant Frequency Converter Using Isolated Circuits And...IJERD Editor
-LLC resonant frequency converter is basically a combo of series as well as parallel resonant ckt. For
LCC resonant converter it is associated with a disadvantage that, though it has two resonant frequencies, the
lower resonant frequency is in ZCS region[5]. For this application, we are not able to design the converter
working at this resonant frequency. LLC resonant converter existed for a very long time but because of
unknown characteristic of this converter it was used as a series resonant converter with basically a passive
(resistive) load. . Here, it was designed to operate in switching frequency higher than resonant frequency of the
series resonant tank of Lr and Cr converter acts very similar to Series Resonant Converter. The benefit of LLC
resonant converter is narrow switching frequency range with light load[6] . Basically, the control ckt plays a
very imp. role and hence 555 Timer used here provides a perfect square wave as the control ckt provides no
slew rate which makes the square wave really strong and impenetrable. The dead band circuit provides the
exclusive dead band in micro seconds so as to avoid the simultaneous firing of two pairs of IGBT’s where one
pair switches off and the other on for a slightest period of time. Hence, the isolator ckt here is associated with
each and every ckt used because it acts as a driver and an isolation to each of the IGBT is provided with one
exclusive transformer supply[3]. The IGBT’s are fired using the appropriate signal using the previous boards
and hence at last a high frequency rectifier ckt with a filtering capacitor is used to get an exact dc
waveform .The basic goal of this particular analysis is to observe the wave forms and characteristics of
converters with differently positioned passive elements in the form of tank circuits.
The document discusses tunnel diodes and their operation. It explains that tunnel diodes use quantum tunneling effects to allow electrons to pass through a potential barrier. The document then provides energy band diagrams and descriptions of tunnel diode operation under forward and reverse bias. It discusses their applications as oscillators, switches, logic devices and amplifiers. The document also compares tunnel diodes to conventional PN diodes and describes other specialized electronic devices like varactor diodes and photodiodes.
This presentation summarizes an operational amplifier based function generator that can produce sine, square, triangular, and sawtooth waveforms. It describes the working of the square wave generator using an op-amp and capacitor to charge and discharge, producing a switching output. A triangular wave is generated by charging and discharging a capacitor with a constant current. This triangular wave can then be shaped into a sine wave using a diode clipping circuit. The function generator can output different frequencies and amplitudes and is used to test electronic equipment.
The three types of rectifiers in just 18 slides. Learn and enjoy the concepts. This PowerPoint presentation not only tells about the working and principles of rectifiers but also determines the disadvantages and advantages of different rectifiers. This PowerPoint presentation also has circuit diagrams that suit your necessities. This PPT can be written as an answer for a long type of question too.
Vocational Training Report ( Sealdah Power House)shovandey07
The document provides information about the power distribution system at Sealdah Power House in Kolkata, India. It describes the key components of the power house including transformers, switchgear, bus bars, isolators, circuit breakers, and protective relays. The power house receives 6KV high voltage from CESC which is stepped down to 415V by transformers before being distributed to Sealdah railway station for lighting, equipment, and facilities. There is also a backup diesel generator at one of the substations in case of outages.
Main news related to the CCS TSI 2023 (2023/1695)Jakub Marek
An English 🇬🇧 translation of a presentation to the speech I gave about the main changes brought by CCS TSI 2023 at the biggest Czech conference on Communications and signalling systems on Railways, which was held in Clarion Hotel Olomouc from 7th to 9th November 2023 (konferenceszt.cz). Attended by around 500 participants and 200 on-line followers.
The original Czech 🇨🇿 version of the presentation can be found here: https://www.slideshare.net/slideshow/hlavni-novinky-souvisejici-s-ccs-tsi-2023-2023-1695/269688092 .
The videorecording (in Czech) from the presentation is available here: https://youtu.be/WzjJWm4IyPk?si=SImb06tuXGb30BEH .
Simulation of SPWM based Z-Source InverterIOSR Journals
1) The document presents a simulation of a SPWM based Z-source inverter. Z-source inverters can boost or buck the output voltage from a DC supply, overcoming limitations of traditional voltage source inverters.
2) MATLAB/Simulink models were developed for a Z-source inverter feeding resistive, inductive, and motor loads. Simulation results validated that the Z-source inverter has lower total harmonic distortion than traditional voltage source and current source inverters.
3) The Z-source inverter topology was analyzed and its operating principle explained. Sinusoidal pulse width modulation was used for switching control. Simulation results showed improved performance of the Z-source inverter over
Pre Final Year project/ mini project for Electronics and communication engine...Shirshendu Das
The document describes a project to construct a full wave rectifier circuit that converts 220V AC input into 5V, -5V, and variable 5V DC output. It includes a center tapped transformer, bridge rectifier using 4 diodes, and voltage regulators. Capacitor filters are used to obtain smooth DC waveforms from the pulsating rectified output. The circuit is simulated using NI Multisim software and experimental results are analyzed. Positive 5V output is obtained using an LM7805 regulator, negative 5V output uses an LM7905 regulator, and an LM317 provides adjustable output.
IRJET- Design and Implementation of Isolated Multi-Output Flyback ConverterIRJET Journal
This document describes the design and implementation of an isolated multi-output flyback converter. A flyback converter uses a single switch and transformer to provide isolated output voltages from an input source. The designed converter uses a toroidal transformer with multiple secondary windings to generate multiple isolated output voltages at fixed levels. Simulation results and specifications for the transformer, switch, and outputs are provided. The flyback converter provides an efficient and low-cost solution for applications requiring multiple isolated low-power DC outputs.
This document discusses power semiconductor devices, including:
1) It provides an overview of common power semiconductor devices like diodes, bipolar transistors, thyristors, MOSFETs, and IGBTs and discusses their typical power and frequency ranges.
2) It describes the construction and operation of p-n junction diodes, including their reverse recovery characteristics and how minority carrier lifetime affects on-state voltage and turn-off losses.
3) It discusses the reverse bias behavior of p-n junction diodes and how the peak electric field is related to the avalanche voltage and reverse leakage current.
A Plasma Tweeter is an audio device which uses a pair of electrodes as a source of sound. It has a clear reproduction and Omni directional radiation pattern. A plasma tweeter has a better frequency response than a conventional speaker and does not involve any moving part (diaphragm) and thus has less reverberation and no wear and tear. Plasma tweeters invented earlier were very expensive. This paper presents a plasma audio system which is making the regular audio system more efficient because of the use of the latest plasma tweeter. Here the objective is to create a low cost and more efficient version of the most speakers invented till now with the complete audio system.
1) Power bipolar junction transistors and Darlington transistors are high power versions of conventional transistors used as static switches in power electronics. They have current ratings of several hundred amps and voltage ratings of several hundred volts.
2) Darlington transistors have a higher gain than single transistors, alleviating the need for high base drive currents.
3) Proper operation requires that transistors remain in saturation to avoid high power dissipation, and within safe operating areas defined by maximum voltage, current, and power boundaries.
1. Power bipolar junction transistors and Darlington transistors are high power versions of conventional transistors used as static switches in power electronics. They have current ratings of several hundred amps and voltage ratings of several hundred volts.
2. Darlington transistors have a higher gain than single transistors and are used when higher base currents are needed to adequately turn on the transistor.
3. The safe operating area of a transistor specifies boundaries on its current and voltage ratings to ensure safe operation without damage. Exceeding these boundaries can lead to avalanche breakdown or second breakdown failure mechanisms.
This document analyzes a transistor clamped H-bridge split phase PWM inverter. It presents the circuit diagram of the proposed inverter which uses coupled inductors to prevent short circuits and reduce reverse recovery losses. A double reference single carrier modulation technique is used to generate PWM signals from two reference signals and a triangular carrier, producing a five-level output voltage. Simulation results in MATLAB Simulink show the five-level output voltage waveform and total harmonic distortion of 8.43%, demonstrating reduced harmonics compared to conventional inverters. The proposed inverter topology and modulation control method aim to improve efficiency, reliability and output waveform quality.
The document summarizes different classes of amplifiers, including power amplifiers, class A amplifiers, and class B amplifiers. It describes the main function of power amplifiers as delivering power to the load. It then discusses the single-ended class A amplifier circuit and its low efficiency of less than 30%. Finally, it introduces the class B push-pull amplifier circuit which uses two complementary transistors to conduct alternating half cycles, improving efficiency to around 70%.
Infomatica, as it stands today, is a manifestation of our values, toil, and dedication towards imparting knowledge to the pupils of the society. Visit us: http://www.infomaticaacademy.com/
This document contains questions and answers related to power electronics topics like phase controlled converters. Some key points:
- Phase controlled rectifiers convert fixed AC voltage to variable DC voltage by controlling the firing delay angle. Common applications include motor drives, traction systems, and process control.
- Freewheeling diodes improve input power factor and output current waveform quality in controlled rectifiers.
- Single phase bridge converters have advantages over midpoint converters like lower peak inverse voltages on SCRs and lower transformer ratings.
- Firing circuits for line commutated converters include UJT, cosine wave crossing pulse timing control, and digital schemes.
- Six-pulse converters have simpler commutation and reduced lower order
This document describes improvements to cyanine dyestuffs, specifically those useful for sensitizing photographic silver halide emulsions. The cyanine dyestuffs are obtained by reacting a terazole quaternary salt with a 5 or 6-membered heterocyclic nitrogen compound or a heterocyclic nitrogen ketomethylene nucleus. The resulting products have general formulas IV or V, representing cyanine dyes that may exist in different resonance forms. The dyes described contain substituents like alkyl, cycloalkyl, aryl, and heterocyclic groups.
This document contains questions and answers related to power electronics devices and converters. It begins with definitions of key power electronics terms:
- IGBT is popular due to lower switching losses and smaller snubber circuit requirements.
- Thyristors can be turned on through forward voltage, gate, dv/dt, temperature, or light triggering.
- Power diodes have higher voltage, current, and power ratings than signal diodes due to a drift region construction.
- IGBTs, power MOSFETs, and power BJTs are voltage, voltage, and current controlled devices respectively due to how their output current is controlled by their input signals.
- There are N-channel and P-channel
Hardware Analysis of Resonant Frequency Converter Using Isolated Circuits And...IJERD Editor
-LLC resonant frequency converter is basically a combo of series as well as parallel resonant ckt. For
LCC resonant converter it is associated with a disadvantage that, though it has two resonant frequencies, the
lower resonant frequency is in ZCS region[5]. For this application, we are not able to design the converter
working at this resonant frequency. LLC resonant converter existed for a very long time but because of
unknown characteristic of this converter it was used as a series resonant converter with basically a passive
(resistive) load. . Here, it was designed to operate in switching frequency higher than resonant frequency of the
series resonant tank of Lr and Cr converter acts very similar to Series Resonant Converter. The benefit of LLC
resonant converter is narrow switching frequency range with light load[6] . Basically, the control ckt plays a
very imp. role and hence 555 Timer used here provides a perfect square wave as the control ckt provides no
slew rate which makes the square wave really strong and impenetrable. The dead band circuit provides the
exclusive dead band in micro seconds so as to avoid the simultaneous firing of two pairs of IGBT’s where one
pair switches off and the other on for a slightest period of time. Hence, the isolator ckt here is associated with
each and every ckt used because it acts as a driver and an isolation to each of the IGBT is provided with one
exclusive transformer supply[3]. The IGBT’s are fired using the appropriate signal using the previous boards
and hence at last a high frequency rectifier ckt with a filtering capacitor is used to get an exact dc
waveform .The basic goal of this particular analysis is to observe the wave forms and characteristics of
converters with differently positioned passive elements in the form of tank circuits.
The document discusses tunnel diodes and their operation. It explains that tunnel diodes use quantum tunneling effects to allow electrons to pass through a potential barrier. The document then provides energy band diagrams and descriptions of tunnel diode operation under forward and reverse bias. It discusses their applications as oscillators, switches, logic devices and amplifiers. The document also compares tunnel diodes to conventional PN diodes and describes other specialized electronic devices like varactor diodes and photodiodes.
This presentation summarizes an operational amplifier based function generator that can produce sine, square, triangular, and sawtooth waveforms. It describes the working of the square wave generator using an op-amp and capacitor to charge and discharge, producing a switching output. A triangular wave is generated by charging and discharging a capacitor with a constant current. This triangular wave can then be shaped into a sine wave using a diode clipping circuit. The function generator can output different frequencies and amplitudes and is used to test electronic equipment.
The three types of rectifiers in just 18 slides. Learn and enjoy the concepts. This PowerPoint presentation not only tells about the working and principles of rectifiers but also determines the disadvantages and advantages of different rectifiers. This PowerPoint presentation also has circuit diagrams that suit your necessities. This PPT can be written as an answer for a long type of question too.
Vocational Training Report ( Sealdah Power House)shovandey07
The document provides information about the power distribution system at Sealdah Power House in Kolkata, India. It describes the key components of the power house including transformers, switchgear, bus bars, isolators, circuit breakers, and protective relays. The power house receives 6KV high voltage from CESC which is stepped down to 415V by transformers before being distributed to Sealdah railway station for lighting, equipment, and facilities. There is also a backup diesel generator at one of the substations in case of outages.
Main news related to the CCS TSI 2023 (2023/1695)Jakub Marek
An English 🇬🇧 translation of a presentation to the speech I gave about the main changes brought by CCS TSI 2023 at the biggest Czech conference on Communications and signalling systems on Railways, which was held in Clarion Hotel Olomouc from 7th to 9th November 2023 (konferenceszt.cz). Attended by around 500 participants and 200 on-line followers.
The original Czech 🇨🇿 version of the presentation can be found here: https://www.slideshare.net/slideshow/hlavni-novinky-souvisejici-s-ccs-tsi-2023-2023-1695/269688092 .
The videorecording (in Czech) from the presentation is available here: https://youtu.be/WzjJWm4IyPk?si=SImb06tuXGb30BEH .
Nunit vs XUnit vs MSTest Differences Between These Unit Testing Frameworks.pdfflufftailshop
When it comes to unit testing in the .NET ecosystem, developers have a wide range of options available. Among the most popular choices are NUnit, XUnit, and MSTest. These unit testing frameworks provide essential tools and features to help ensure the quality and reliability of code. However, understanding the differences between these frameworks is crucial for selecting the most suitable one for your projects.
In the rapidly evolving landscape of technologies, XML continues to play a vital role in structuring, storing, and transporting data across diverse systems. The recent advancements in artificial intelligence (AI) present new methodologies for enhancing XML development workflows, introducing efficiency, automation, and intelligent capabilities. This presentation will outline the scope and perspective of utilizing AI in XML development. The potential benefits and the possible pitfalls will be highlighted, providing a balanced view of the subject.
We will explore the capabilities of AI in understanding XML markup languages and autonomously creating structured XML content. Additionally, we will examine the capacity of AI to enrich plain text with appropriate XML markup. Practical examples and methodological guidelines will be provided to elucidate how AI can be effectively prompted to interpret and generate accurate XML markup.
Further emphasis will be placed on the role of AI in developing XSLT, or schemas such as XSD and Schematron. We will address the techniques and strategies adopted to create prompts for generating code, explaining code, or refactoring the code, and the results achieved.
The discussion will extend to how AI can be used to transform XML content. In particular, the focus will be on the use of AI XPath extension functions in XSLT, Schematron, Schematron Quick Fixes, or for XML content refactoring.
The presentation aims to deliver a comprehensive overview of AI usage in XML development, providing attendees with the necessary knowledge to make informed decisions. Whether you’re at the early stages of adopting AI or considering integrating it in advanced XML development, this presentation will cover all levels of expertise.
By highlighting the potential advantages and challenges of integrating AI with XML development tools and languages, the presentation seeks to inspire thoughtful conversation around the future of XML development. We’ll not only delve into the technical aspects of AI-powered XML development but also discuss practical implications and possible future directions.
5th LF Energy Power Grid Model Meet-up SlidesDanBrown980551
5th Power Grid Model Meet-up
It is with great pleasure that we extend to you an invitation to the 5th Power Grid Model Meet-up, scheduled for 6th June 2024. This event will adopt a hybrid format, allowing participants to join us either through an online Mircosoft Teams session or in person at TU/e located at Den Dolech 2, Eindhoven, Netherlands. The meet-up will be hosted by Eindhoven University of Technology (TU/e), a research university specializing in engineering science & technology.
Power Grid Model
The global energy transition is placing new and unprecedented demands on Distribution System Operators (DSOs). Alongside upgrades to grid capacity, processes such as digitization, capacity optimization, and congestion management are becoming vital for delivering reliable services.
Power Grid Model is an open source project from Linux Foundation Energy and provides a calculation engine that is increasingly essential for DSOs. It offers a standards-based foundation enabling real-time power systems analysis, simulations of electrical power grids, and sophisticated what-if analysis. In addition, it enables in-depth studies and analysis of the electrical power grid’s behavior and performance. This comprehensive model incorporates essential factors such as power generation capacity, electrical losses, voltage levels, power flows, and system stability.
Power Grid Model is currently being applied in a wide variety of use cases, including grid planning, expansion, reliability, and congestion studies. It can also help in analyzing the impact of renewable energy integration, assessing the effects of disturbances or faults, and developing strategies for grid control and optimization.
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US3153766.pdf
1. Oct. 20, 1964 , R. E., TANCINCO 3,153,766
MODE OF OPERATION OF THE FENTODE OR TETRODE TUBE
IN THE OUTPUT STAGE OF AN AUDIO POWER AMPLIFIER
Filed Sept. 8, 1961
ANODE CATHOD
YAN A/
DODE INVENTOR.
FIG.5 -N
(ewi? Sauveto
2. UnitedStates Patent Office 3,153,766
Patented Oct. 20, 1964
3,553,766
MODE OF OSPERATION OF THE PENTO DE OR
TETRODE TUBE IN THE OUTPUT STAGE OF
AN AUDIO POWER AMPLEFER
Renato E. Tancinco, Meycauayan, Bulacan, Philippines
Fied Sept. 8, 1961, Ser. No. 36,817
Claims priority, application Philippines Sept. 2, 1960
5 Claims. (C. 330-22)
This invention relates to a new concept in the mode
of operation of a pentode or tetrode power tube in the
output stage of an audio frequency amplifier. Up to
the present stage of the art, the output tubes in an audio
frequency amplifier operate only under one set of char
acteristics which is determined by the mode of opera
tion assigned to them. The following are the modes of
operations under which a pentode or tetrode power tube
may be made to operate:
(1) Triode connected pentode or tetrode output stage.
(2) Distributed load pentode or tetrode output stage or
the so called "Uutra Linear Amplifiers.'
(3) Straight pentode or tetrode output stage.
(4) Unity coupled output stage.
(5) “Extended Class A Amplifier” using a pair of triode
connected push pull pentode or tetrode in parallel
with another pair of the same type of tubes con
nected as straight pentode or tetrode.
The sixth mode of operation is offered by the under
signed and is the subject of this patent application. In
this new mode of operation, the output pentode or
tetrode tube alternately operates between the two sets
of characteristics assigned to them. These two sets of
characteristics are determined by the position of the two
taps on the plate winding of the output transformer to
which the anodes of the back to back connected diodes,
feeding the screen grid of the said power tube, are con
nected. The particular set of characteristics under which
the output tube operates is determined by the polarity
of the grid signal voltage relative to the quiescent poten
tial of the control grid, otherwise known as the grid bias.
Some of the objectives of this invention are as follows:
(1) To obtain high quality reproduction of sound with
out the necessity of using expensive special output
transformers or resorting to complex circuitry.
(2) To be able to obtain the most power output avail
able for a given power output tube and a given B
supply voltage, commensurate with high plate circuit
efficiency, low distortion, and low power consump
tion during the absence of signal or during idling.
(3) To attain the above objectives without the neces
sity of using more than one pair of power output tubes
or more than one power Supply or B-Supply.
(4) To reduce the output impedance of the power out
put stage before the application of any inverse feed
back.
(5) To be able to attain the above objectives without
the need for very high signal grid drive voltage to the
power output tubes.
(6) To give the amplifier designer a free hand in the
design of the whole amplifier. The said freedom is
achieved by virute of the following:
(a) Absence of inherent inverse feedback in the
output stage. The manner of application of the
inverse feedback is left entirely to the amplifier
designer.
(b) The designer is free to choose any type of
pentode or tetrode power tube for the power
amplifier stage.
(c) The choice of the position of the taps on the
plate winding of the output transformer is the
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privilege of the amplifier designer. The positions
chosen will determine the two different sets of
characteristics between which the power output
tube will alternately operate.
The New Circuit
A good amplifier must not only be good in perform
ance but it must meet the requirements of the manu
facturer, the amplifier designer, and above all satisfy the
ultimate user, i.e., the owner.
it is a fact that in the reproduction of music, the
high power peaks are relatively few and of very short
durations, that, most of the time the amplifier may be
considered as idling. Low consumption of power dur
ing idling is therefore of paramount importance. An
amplifier is usually rated at the maximum power that it
can deliver during these peaks, with a minimum of dis
tortion and good stability. The maximum power that
a pair of power tubes can deliver is usually limited by
the maximum plate dissipation rating of the said power
tube. To get therefore the most out of a pair of power
tubes, the plate circuit efficiency of output stage should
be high. It is also very desirable to obtain high power
outputs without the necessity of using very high signal
grid drive voltages. In other words, the power sensi
tivity of the output stage must be high. It is therefore
clear that Class B operated pentode or tetrode power
tubes appear to be ideal for the output stage. The re
quirement of low distortion in output stages using the
conventional Class B pentode or tetrode power tubes is,
however, not easily met. The cause is the presence of
a form of distortion, called the notch distortion, which
occurs as a notch or fuzziness in the output signal wave
form. In reality, this fuzziness in the output signal
waveform is a form of shock excited self oscillation at
some ultra-sonic frequency in the plate winding of the
output transformer. The leakage inductance between
the plate windings of the output transformer forms an
oscillatory circuit in combination with the winding
capacitance and other stray capacitances. This oscil
latory circuit is shock excited into self-oscillation every
time the plate current of the power tube is driven to
cut off. Unfortunately the frequency of this fuzziness
or notch distortion is so high that it is beyond the effec
tive control of the inverse feedback loop that may be
applied in the amplifier. Furthermore, the plate cur
rent of the power tube which is the most logical part
of the amplifier that can prevent the said distortion, has
been driven to cut off. The said power tube, being then
inactive, is therefore not in a position to prevent the
occurrence of the said notch distortion. So far there
are two successful solutions to the problem of prevent
ing the occurrence of the notch distortion. They are
exemplified in the Unity Coupled Amplifiers and the
Extended Class A amplifiers. A third solution is offered
by this invention, which is believed to be an entirely
new concept in the mode of operation of pentode or
tetrode power tubes in the output stage of an audio power
amplifier. -
The foregoing objectives will become more apparent
from the following detailed description of various em
bodiments of the invention and from the accompanying
drawings wherein:
FIG. 1 is an electrical schematic diagram illustrating
a push-pull tetrode power amplifier incorporating the
switching diodes in circuit between the screen grids and
output transformer.
FIGS. 2-4 are views similar to FIG. 1 but illustrating
various modifications for connecting in the switching
diodes; and
FIG. 5 is a detail of one of the switching diodes in
3. 3,153,766
d
dicating the convention observed in designating its cath
ode and anode components.
Referring to FIG. 1 of the annexed drawing which
forms a part of this patent application, there is shown a
push pull tetrode power amplifier, which is operated as
a conventional Class B output stage except for the man
ner in which the screen grids of the power tetrodes
V-a and V-b are fed. In a conventional output stage
using Class B pentodes or tetrodes, the screen grids of
the tubes are fed by the B-Supply for the plates or, if
a different voltage is required for the screen grids, by a
separate screen grid power supply. It will be noticed
that the screen grids of the power tetrode tubes V-a
and V-b are connected to the common cathodes of two
pairs of back to back connected diodes, V-, V-2, V-3
and V-4. The anodes of the diodes V- and V-2 are
connected respectively to taps No. 1 and No. 2 on the
corresponding plate winding of the output transformer
T-1 and similarly the diodes V-3 and W-4. When the
tetrode V-a grid is driven to the positive direction by
the signal, the plate swings to the negative direction
relative to the B-Plus terminal of the B-Supply. Such
a situation makes tap No. 2 on the plate winding more
positive than the tap No. 1, causing diode V-1 to cut
off -while diode V-2 remains conducting. Diode V-2
therefore, effectively ties the screen grid to tap No. 2
on the plate winding. Tube V-a will therefore behave
in the same manner as when its screen grid is per
manently connected to tap No. 2 of the plate winding of
the output transformer. On the negative half of the
signal wave, the grid of the power tetrode V-a is driven
to the negative direction. The plate of the tube V-a
then swings to the positive direction relative to the B
Plus terminal of the B-Supply. Tap No. 1 therefore
of the plate winding of the output transformer then
becomes more positive than tap No. 2, thus causing
diode V-2 to cut off and diode V-E to conduct instead.
The conduction of diode V-1 effectively ties the screen
grid of tube V-a to tap No. 1 in plate winding of the out
put transformer T-1. Tube V-a then, will therefore be
have as if its screen grid is permanently connected to
tap No. 1 of the plate winding of the output transformer.
In the absence of a signal, the two diodes V-1 and V-2
are both conducting and are sharing the screen grid cur
rent drain of the tube V-a. It can be seen therefore
that the characteristics of the power tetrode V-a during
the positive half of the grid signal voltage is entirely
different from those, during the negative half of the grid
signal voltage. The tube V-a therefore automatically
operates alternately between two different sets of char
acteristics, with the aid of diodes V-1 and V-2. The
polarity of the grid signal voltage determines under
which set of characteristics the power tetrode V-a will
operate. It must be noted however that the positions of
taps No. 1 and No. 2 on the plate winding of V-a are
identical respectively to those of the taps No. 4 and No.
3 on the plate winding of V-b. The proper positions
of the taps on the plate windings are left to the discretion
of the amplifier designer. They can be anywhere from
the B-Plus terminal to the plate terminal of the plate
windings. The limiting positions of the taps is shown
in FIG. 2 of this drawing. Here, tap No. 1 is at the
plate terminal of the plate winding of the output trans
former while the tap No. 2 is at the B-Plus terminal of
the B-Supply. In FIG. 2 of the drawing, power tetrode
V-a operates as a straight tetrode on the positive halves
of the grid signal voltage, while during the negative
halves, it operates as a triode. On the positive half of
the grid signal voltage, the screen grid of tube V-a is
tied to the B-Plus terminal of the B-Supply while on the
negative half of grid signal voltage, the screen grid is
connected to its plate. Automatic Switching is ac
complished by the back to back connected diodes V-1
and V-2. In this mode of operation, the output trans
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former T-2 can be any standard output transformer
ordinarily available. Even though tube V-a is biased
to the projected plate current cut off value like in con
ventional Class B amplifiers, its plate current can never
reach cut off. The action of the control grid in forcing
a plate current cut off during the negative halves of
the grid signal voltage, is effectively counteracted by the
rise in the potential of the screen grid which is then
tied to the plate due to the conduction of diode V-1.
The low plate impedance of the then triode connected
V-a effectively damps the plate winding connected to
it, thus preventing the winding from ever being shock
excited into self-oscillation. The possibility therefore,
of the occurrence of notch distortion, can entirely be
precluded. The fact, that the tube V-a is connected
as a tetrode during the positive halves of the grid
signal voltage, makes it possible to obtain a relatively
large power output at high plate circuit efficiency and
at very low power consumption during idling, like in
the conventional Class B tetrode power amplifiers. We
therefore have now an amplifier that performs very
much like a conventional Class B tetrode amplifier with
all its advantages but without its disadvantages, i.e., the
notch distortion. It should be noted however, that the
grid drive voltage requirements are low and are the same
as when the output tubes are connected as in a conven
tional Class B tetrode power amplifier.
In the prototype amplifier that was tried by the under
signed a pair of 807's were used for V-a and V-b and
one pair of 6 x 4's were used in place of the diodes
V-A, V-2, V-3 and V-4. The common cathodes of the
6 x 4's feed the screen grids of the 807's. The output
transformer used was a “Merit' 55 watt P.A. output
transformer with a plate to plate rated load of 3,300
ohms. The circuit used is shown on FIG. 2 of the draw
ing. Although the output stage operates as a Class B
tetrode power amplifier, the output impedance, without
any inverse feed back is low and the same as that of a
triode amplifier. This low output impedance is the re
sult of the alternate Tetrode-Triode operation of the
output tubes.
FIG. 3 of the drawing shows a mode of operation in
which the power output tubes operates as a distributed
load tetrodes or "Ultra Linear' amplifier during the
positive halves of the grid signal voltage and as triodes
during the negative halves of the grid signal voltage. As
in FIG. 2, the possibility of the occurrence of notch dis
tortion in this case is non-existent.
The circuit in FIG. 4 is the same as in FIG. 2 except
that the anode of the diode V-1 is connected to the
tap No. 1 on the plate winding of the output transformer
T-4. In this case the positive voltage applied to the
Screen grid of the tube V-a thru diode V-1 during
the negative half of the grid signal voltage is just enough
to prevent the plate current of the tetrode V-a from
reaching the cut of point during the maximum power
output ofthe amplifier.
In the foregoing discussions, the principles involved
in the operation of this new amplifier can be fully un
derstood. In regards to the diodes V-1, V-2, V-3 and
V-4, semi-conductor diodes may be used in lieu of
thermionic diodes, provided however, that the peak in
verse voltage of the diodes are not exceeded during the
delivery of maximum power to the load or when the
amplifier is unloaded while in operation.
Advantages of This Invention
The advantages that may be derived from the appli
cation of this invention in the manufacture of high qual
ity audio frequency power amplifiers may be summed up
as follows:
(1) The application of this invention may be con
sidered the most practical approach to the design and
manufacture of high quality reliable audio power am
plifiers that are capable of relatively high power output
4. 3,153,766
s
with low distortion, high plate circuit efficiency, low power
consumption during idling, and at a reasonably low cost.
(2) The amplifier does not require specially designed
output transformers. In fact, standard output trans
formers commonly available can be successfully used.
There is no need for sectionalized and intermeshed plate
windings that are required for the successful operation
of the conventional distributed load or "Ultra Linear”
amplifiers, nor is it necessary to use a special, bi-filar
wound output transformer as in the case of the unity
coupled McIntosh and Gow amplifier. The presence of
the full B-Supply voltage between the turns of this bi
filar windings greatly affects the reliability of the whole
amplifier.
(3) The amplifier requires only one power supply
and this power Supply is operated at signal ground po
tential. The "Extended Class' A-2 amplifier requires an
additional well regulated screen grid power supply for
its successful operation. The "Circlotron Amplifier' of
Electro Voice, Inc. requires two separate and identical
power Supplies, one for each power output tube, and
furthermore, these power supplies are operated above
signal ground potential. The additional cost of the ex
tra power Supply is worth considering, and moreover,
operating the power supplies above signal ground poten
tial can affect the frequency characteristics and the sta
bilityofthe whole amplifier.
(4) Only one pair of power output tubes are required
for the successful operation of this amplifier. To equal
the power output of a conventional amplifier using one
pair of power output tubes, the "Extended Class A Am
plifier' requires two pairs of power output tubes. Con
sidering the present cost of good audio power output
tubes, the additional cost of the extra pair of power
tubes is certainly worth savings,
(5) The output impedance of this amplifier before
the application of any inverse feed back is low and the
Same as that of a triode power amplifier. The alternate
operation of the power output tubes as a triode or near
triode during the negative halves of the grid signal volt
age accounts for the low output impedance of this am
plifier.
(6) Elimination of the notch distortion is accomplished
in this amplifier without resorting to Unity Coupling or
Extended Class A operation with their attendant disad
Vantages.
(7) Compared to Unity Coupled amplifiers, the sig
nal grid drive voltage requirement of this amplifier is
very low. It is not necessary to design a special driver
stage to deliver the high signal voltages at low distortion
as is called for in the Unity Coupled amplifiers. It is
very possible for the driver stage to contribute most of
the distortion in the output of an otherwise distortion
free Unity Coupled amplifier. Specially designed driver
stages can increase the cost of an amplifier and add to
the complexity of the circuit.
(8) This amplifier is not very particular as to the type
of the power output tube. The manufacturer or the am
plifier designer is free to choose any power pentode or
tetrodefor the outputstage of thisamplifier.
(9) The absence of inherent inverse feedback in the
output stage of this amplifier is a distinct advantage. The
amplifier designer has therefore a free hand in the choice
of the manner in which the inverse feedback may be
applied. Inherent inverse feedback in the output stage
is inevitable in Unity Coupled amplifiers. This inherent
feedback accounts for the very high grid drive signal
voltage requirements of Unity Coupled amplifiers.
(10) The fact that the notch distortion is non-existent
in the amplifier, makes it advantageous to set the grid
bias of the power output tubes to the projected cut off
value of the plate current. The amplifier is therefore
capable of relatively high power output at high plate cir
cuit efficiency, attendant to low power consumption dur
ing idling. This will mean a very much longer life for
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the power output tubes, less power consumption and sav
ings in money for both the manufacturer and the end user.
(11) The choice ofthe mode ofoperation of the power
output tubes is entirely left to the discretion of the ampli
fier. The desired two different sets of characteristics
under which the power output tubes will alternately op
erate may be obtained by the amplifier designer with the
proper choice of the points in the plate windings of the
output transformer to which the anodes of the back to
back connected diodes are to be connected. The ampli
fier designer is therefore completely free to choose the
two different sets ofcharacteristics under which the power
output tubes will alternately operate to obtain his desired
results.
(12) The circuitry of this amplifier is very simple.
The simplicity of the circuitry makes it easy for the man
ufacturer to duplicate the performance of the original
model during the production run. Simplicity of the cir
cuit contributes to the stability and reliability of the whole
amplifier.
In class B power amplifiers, the push pull output tubes
alternate in the delivery of power to the load. The
power output tubes deliver power to the load, only dur
ing the positive half of the grid signal voltage. During
the negative half of grid signal voltage, the plate current
of the power tube is cut off. The power output tube is
then inactive and therefore serving no useful purpose.
The essence of this invention is to make the said inactive
tube do some useful work, i.e., act as an effective damp
ing element to the then inactive plate winding of the
output transformer. During the negative halves of the
grid signal voltage, the output tube is operated as a tri
ode or near triode to prevent its plate current from ever
reaching the cutoff point and to act as a low impedance
shunt across the inactive plate winding of the output
transformer. The action of this, otherwise inactive tube
during the negative halves ofthe gridsignal voltage, effec
tively prevents the occurrence of the notch distortion.
I claim:
1. As an output stage for a push-pull audio amplifier
the combination comprising first and second tubes con
nected for push-pull anode loaded operation, each said
tube including a cathode, anode, signal grid and a screen
grid, a push-pull output transformer, said output trans
former including first and second primaryportions respec
tively connectedto and loading the anodes ofsaidfirstand
Second tubes, first and second pairs of common-cathode
back-to-back arranged diodes connected in shunt respec
tively with said first and second primary portions of said
Output transformer, and circuit means respectively con
necting the common cathodes of said first and second
pairs of diodes to the respective screen grids of said first
and Second tubes foreffecting automatic switching ofeach
said Screen grid alternately between the terminals of the
corresponding primary portions of said output trans
former.
2. A push-pull audio amplifier output stage as defined
in claim 1 wherein said first and second portions of the
primary of said output transformer are provided respec
tively with first and second pairs of taps, and said first
and second pairs of diodes are connected respectively to
said pairs of taps for shunting the same to thereby effect
said automatic Switching of each said screen grid alter
nately between said taps.
3. A push-pull audio amplifier output stage as defined
in claim 1 wherein said first and second pairs of diodes
are connected respectively in shunt between the apper
taining anode terminals and the positive terminal ofthe
power Supply connected between the cathodes and a point
on Said transformer primary intermediate the first and
second portions thereof to thereby effect said automatic
Switching of each said screen grid alternately between
the apertaining anode terminal and said power Supply
terminal.
4. A push-pull audio amplifier output stage as defined
5. 3,153,766
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in claim 1 wherein said first and second portions of the
primary of said output transformer are each provided
with a tap and said first and second pairs of diodes are
connected respectively in shunt between the appertaining
tap and the anode terminal of the appertaining tube to
thereby effect said automatic switching ofeach said screen
grid alternately between the corresponding tap and the
anode terminal.
5. A push-pull audio amplifier output stage as defined
in claim 1 wherein said first and second portions of the
primary of said output transformer are each provided
with a tap, and said first and second pairs of diodes are
0.
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connected respectively in shunt between the appertaining
tap and the positive terminal of the power supply con
nected between the cathodes and a point on said trans
former primary intermediate the first and second portions
thereof to thereby effect said automatic switching of each
said screen grid alternately between the corresponding
tap and said power supply terminal.
References Cited in the file of this patent
UNITEd STATES PATENTS
Hafler et al. ------------- June 7, 1955
Gabor et al. ------------- Jan. 13, 1959
2,710,312
2,868,896