Questions tagged [power-amplifier]
An electronic amplifier that amplifies a low-power signal in order to make it more suitable for an application that requires higher power (e.g. driving a speaker). Power amplifiers have special challenges compared to lower power amplifiers (e.g. a voltage amplifier, which amplifies a signal's voltage but does not provide much output current capability); such challenges include more board space, cooling components that are dissipating high power, etc.
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Audio amplifier for a physics experiment, how do I make it? [closed]
The experiment includes a mic taking in sound(2KHz-4KHz) and sending it to a DSO. I need an audio amplifier circuit in between that to amplify the signal so it would be visible properly. The ...
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Are there risks to a power amplifier by driving it below its minimum frequency?
I have an RF power amplifier that is rated for operation between 700 and 2700 MHz. What happens if we drive it at a lower frequency, say 600 MHz? Is there an increased risk in damaging the amplifier? ...
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Vacuum tube amp RF plate choke design
I am building a vacuum tube RF power amplifier for SSB. Here is the link for the amplifier.
https://www.qsl.net/vu2awc/ham_radio_india_v/vu2atn_qro/vu2atn.htm
I need to clarify first that I am ...
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Using GU50s in a guitar amp
I have a number of GU50s from Ukraine - they were a soviet copy of the German LS50 and are apparently seen as a good tube on the HiFi side of things. The datasheets are easy to find but the ones I can ...
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How to solder the central pin of the TGA 2214-CP microwave amplifier
Here is datasheet of the TGA 2214-CP amplifier: TGA 2214-CP
The pins can be seen on page 11. It turns out that pin 7 and 9 are very close to the central pin 1, as well as pin 8 and 10 to pin 2 (about ...
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How can a Class E Power Amplifier be built and experimented with safely?
Given that Class E RF amplifiers, even those that generate less than a few watts, can easily generate voltage spikes approaching (or exceeding) 100 V, how can they be homebrew built and experimented ...
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Looking to identify and find an equivalent varistor for a Crest ca9 amplifier
I picked up a Crest ca9 amplifier over the weekend knowing it needed work when I plugged it in And turned it on it. Started letting the smoke out. Long story short, I found a varistor That had blown. ...
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Modern Mobile Transistor Guitar Amps How do they work? [closed]
I wonder how these modern transistor guitar amplifiers work.
Take for example the Roland Cube Street EX.
Max Power Output: 50W (2x25W)
Power Supply: AC Adaptor (DC 13V) or 8x Alkaline/NI-MH AA ...
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Noise observed in QPA2935
I am using a "Pulsed biasing board" which provides the drain signal and gate signal to a power amplifier.
I am interfacing the same with QPA2935 driver amplifier(DA)
Please find the ...
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Audio amplifier for school project
For a school project, we have to explain this design of a audio amplifier. We have only been able to understand to parts marked with colored rectangles.
The design comes from the book audio power ...
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Class AB amplifier voltage amplifier stage
I am design a 1W audio amplifier and i want to have 8V peak to peak output signal but if i increased the R4 resistor then the output signal would be clipped. My input is 0.3V max sinewave. Here is my ...
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Are my power calculations on this MOSFET Power Amplifier accurate?
Thanks to the help of electronics.SE, I've designed my first power amplifier, intended for transmitting CW on 7 MHz.
Before I order parts and build it, I'd request a design review.
One important note:...
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Load is switching between 0V and overcurrent in the pulsed drain biasing circuit for a Power Amplifier
Given below is a block diagram of an evaluation-board.
It is a pulsed biasing board to a PA. It is designed to produce a pulsed-drain and pulsed-gate signal for the biasing of GaN Power Amplifiers.
I ...
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Does a MOSFET draw current from its gate?
I understood that a MOSFET does not draw current from its gate, and only depends on gate voltage. However, this simple MOSFET circuit shows that when R1 is very low (1 ohm), it works fine, but when ...
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What is the purpose of the base inductor on this Class C amplifier?
This Pixie III 7 MHz transceiver uses Q2 as a Class C amplifier. What is the purpose of L1?
The article only says
The value of RF choke L1 is not critical. Since little current passes through it ...
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