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A triode pentode is a thermionic valve, also known as a vacuum tube (USA). It comprises a triode which has three electrodes and a pentode which has five electrodes, both sections of the valve are enclosed in a single glass envelope.
They were often used in domestic audio amplifiers in the 'valve era' where the triode section acted as a preamplifier to increase the amplitude of the low level signal from the input source such as a tape head or a crystal pick-up; and the pentode section provided sufficient power amplification to drive a small loudspeaker.
Minimising the number of valves in such designs significantly reduced the overall power consumption, heat dissipation and manufacturing cost of the equipment. It also reduced the retail price, making record players more affordable to the domestic consumer.
Triode pentodes are still used in some current production, British built Hi Fi amplifiers because, with careful attention to the design, they can be configured to out-perform double triodes (two triodes in a single envelope) in the driver stages.
Submitted by Graham Stannett (Croxley Audio). I would be grateful if you would be kind enough to contact me if you wish to amend this WikiAnswer or if you would like more information regarding valve amplifiers.
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What is a crystal triode?
A crystal triode is the old term for transistor. Crystal diodes were well established by the time transistors were invented, so using vacuum tube terminology, the logical name for a diode whose current could be controlled by a third element was "crystal triode".
What is the full form of TRIAC?
TRIAC is the word derrived from the 2 words TRIode and AC.
What are the advantages of using transistor as an switch instead of diode?
1. A transistor *is* a triode- this is the general name for any three-electrode electronic device. 2. Most people understand "triode" to mean a tride vacuum tube/valve. 3. The transistor (i) needs no heated filament/cathode, so it uses much less power than a valve triode, (ii) because of (i), transistors do not "burn out" with age, so they have much longer lifetimes, are much more reliable, and generate much less waste heat, (iii) transistors can operate at much lower power than triode valves, and at much higher frequencies, (iv) transistors can be made much smaller than triodes, by a factor of many tens of thousands, (v) from early on, transistors were much cheaper than triode valves.
What is a TRIODE and what are its uses?
A triode is a vacuum-tube (US) aka valve(UK) with three electrodes : an anode, a cathode and a grid. The cathode is heated electrically which boils off a cloud of electrons. The anode is made positive ( typ. 100-500V) which attracts the electrons towards it. The grid is an open structure, usually of thin wires, placed between the anode and cathode, but nearer the cathode. If a negative voltage is applied to the grid the current flow through the tube is reduced. The more negative, the less current. Prior to the development of transistors, tubes were used for all things in radio,TV and electronics. Different tubes had different numbers of electrodes; the triode was particularly suited to high power amplifiers, especially at radio frequencies. Triodes are still used today by shortwave radio stations, and for RF heating equipment.
What is dual triode tubes?
It's a thermionic valve/electron tube with *two* triodes in the one envelope. Examples: 3A5, 6J6, 6SN7/6SL7, 12AU7/12AX7, ECC32, ECC82.
What is triod?
A triode pentode is a thermionic valve, also known as a vacuum tube (USA). It comprises a triode which has three electrodes and a pentode which has five electrodes, both sections of the valve are enclosed in a single glass envelope. They were often used in domestic audio amplifiers in the 'valve era' where the triode section acted as a preamplifier to increase the amplitude of the low level signal from the input source such as a tape head or a crystal pick-up; and the pentode section provided sufficient power amplification to drive a small loudspeaker. Minimising the number of valves in such designs significantly reduced the overall power consumption, heat dissipation and manufacturing cost of the equipment. It also reduced the retail price, making record players more affordable to the domestic consumer. Triode pentodes are still used in some current production, British built Hi Fi amplifiers because, with careful attention to the design, they can be configured to out-perform double triodes (two triodes in a single envelope) in the driver stages. Submitted by Graham Stannett (Croxley Audio). I would be grateful if you would be kind enough to contact me if you wish to amend this WikiAnswer or if you would like more information regarding valve amplifiers.
What problem in Triode vacuum tubes is solved by the screen grid in Tetrode vacuum tubes?
The screen grid shields the control grid from the plate, reducing capacitance and the Miller Effect, improving performance at high frequencies.It *also* greatly increases the intrinsic ("natural") gain.This is the amplification factor, "mu".A triode has a maximum mu of around 100, and as little as 2.0, depending on the valve type.A tetrode/pentode has a mu in excess of 500, often in the thousands.However, you won't usually find a specification for mu in tetrode/pentode data sheets, as it's impractical to design circuits with this amount of gain.Around 300~350 is the practical maximum.
What is an equivalent diode of a triode valve?
Hard to answer this one.The triode is a diode with a control electrode (the grid) added.The only useful answer is that a triode is a voltage-controlled doide.Try asking the question so that it can be answered more usefully.
What does 127 stand for in BY 127 diode?
BIPOLAR A2 It does not stand for anything. It is a maker's designation mark, a throwback from the thermionic tube (valve) days. The letters in front of the number used to indicate the heater voltage and the type of internals (triode, pentode etc) B used to indicate that it was a semiconductor, not a tube. There are different designations around the world, for the same equivalent device, American, European and Japanese.
What does BY stand for in BY 127 diode?
BIPOLAR A2 It does not stand for anything. It is a maker's designation mark, a throwback from the thermionic tube (valve) days. The letters in front of the number used to indicate the heater voltage and the type of internals (triode, pentode etc) B used to indicate that it was a semiconductor, not a tube. There are different designations around the world, for the same equivalent device, American, European and Japanese.
What are the following vacuum tube types - 45 - 80 - 125A - 1C5 - 5Y3 - 5U4 - 12SA6?
45 - triode power amplifier 80 - fullwave rectifier 125A - - can't find data 1C5 - pentode power amplifier 5Y3 - equivalent to 80 5U4 - higher-rated version of 80/5y3 12SA6 - - can't find data - did you mean *12sa7* pentagrid converter
Why you use tetrode instead of triode?
a tetrode is used when you need a screen grid tube, but a suppressor grid tube can't be used.OK, but the question was "why use a tetrode instead of a triode?"So, the answer...1. A tetrode has a higher voltage/power gain than a triode.2. A tetrode has less anode-grid feedback capacitance than a triode, and can operate in common-cathode radio frequency circuits without the neutralisation (or other corrective circuitry) that is needed by a triode.
How a triode works as basic amplifier?
A triode works as a basic amplifier by the use of radio waves. The radio waves produce a heat that is amplified.
Can be a triode tube PET 25W be damage due to electric fluctuation?
Can a triode tube PET 25W be damaged due to electric fluctuation
What is a crystal triode?
A crystal triode is the old term for transistor. Crystal diodes were well established by the time transistors were invented, so using vacuum tube terminology, the logical name for a diode whose current could be controlled by a third element was "crystal triode".
Who invented the triode?
In 1906 Lee De Forest, an American engineer (often called the "father of radio"), invented the three-element vacuum tube, or triode.
What is an electronic vacuum valve with three electrodes?
Triode
