A preamp takes in very weak DC voltages or audio or RF signals and amplifies them enough to be used by a more conventional amplifier. Input may be in microvolts and output maybe 1 volt RMS or peak. They are often specific to amplify DC, LF/audio, RF or microwave bands. No preamp can cover DC to microwave bands and have good parameters at both DC and RF without software offset and gain correction.
Questions tagged [preamp]
201 questions
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What is ALC on a preamp?
I have a preamp rescued from an old stereo: BA3308
It has a pin "ALC" and the data sheet keeps going on about how splendid this ALC is and how it has a built-in ALC diode and such.
Nowhere does it tell you what ALC is, or how you should use this ALC…
Majenko
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LM358 Electret microphone preamp
I am trying to make an electret mic preamp with lm358.
here are the pspice simulation results.
I measured the voltage of the pins and the values were simulated exactly like the sample.
I tried with 5 to 11 volts.
Regardless of the slight noise,…
Eddi
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How does the transient protection in this AC-coupled preamplifier work?
I'd like to build a preamplifier for measuring the noise of very quiet linear regulators using a baseband spectrum analyzer. I found this page, which presents a few designs for this and looks promising. However, I'm having some trouble understanding…
MattHusz
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Preamp Ground Loop Problem
I have built the blue circuit above for my microphone but the one of the problems I'm facing is that when I connect it to my laptop's audio input, it creates a humming sound. My assumption is there is a lot of noise whenever I pug it into my…
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Micro audio preamp with low consumption [SOLVED]
The audio output for all of my devices/computers is too small to push my speakers to the maximum.
I want to build a very small audio preamplifier to hook between the computer and speaker to boost the signal a bit. The output should be about 0.5V
Can…
IceCold
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