An amplifier can be used to adapt the range of the signal to a requirement, to make it more robust for transmission, or to satisfy interface requirement (like input/output impedance)

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1answer
18 views

How Much Current Draw From Speakers/Amplifier?

So I plan on using the VS1053 Codec connected to a class D Amp (2 x 2.8W channel) with two 3W 4 Ohm speakers. If I supply 5V to this setup, what would the current draw be at full use? Codec: ...
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4answers
161 views

Is it voltage or power of the signal amplified when the opamp amplification is given in dB unit?

Today, one of my colleague said that he entered a preliminary examination in a company after his job application. One of the questions is exactly "Design a non-inverting amplifier with 20dB gain.". ...
2
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1answer
31 views

AoE3: Grounded Emitter Amplifier Distortion

I'm trying to understand a passage in the 3rd edition of Art of Electronics which explains the distortion of grounded emitter, common collector amplifiers vs. those using an emitter resistor (ch. 2, ...
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0answers
36 views

Is it safe to run power cables above a 1100 watt amplifier?

I'm setting up audio equipment wherein a power amplifier running on 230V with 1100 Watts is involved. Due to the construction I need to run 3 power cords on top of the amp. The power strip is located ...
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0answers
46 views

Distortion in an amplifier

I need help with this exercise: "Given a common-source amplifier without any charge, it can be seen that there's cut-off distortion. How can you fix that, without changing the gain of the amplifier?" ...
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3answers
130 views

60Hz “click” or clipping noise when differential amplifier is surrounded by salt water

I am a graduate student attempting to take electrophysiology recordings from a lobster under water. In the current set up I am using, two differential amplifier boards are attached the the lobster's ...
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0answers
94 views

Operational Amplifier frequency problem

I am using an operational amplifier in an inverting configuration with a gain of 10. (-R2/R1= 10), with a high cut-off frequency of almost 30 Mhz. However, while testing whenever I apply an input ...
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1answer
67 views

What is wrong with my guitar amp?

I found this 1W guitar amp design on the Internet: http://www.diale.org/punch.html And I am trying to build it on the protoboard. I could not find the IC TDA7052, instead I've got the a TDA7052B. ...
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0answers
47 views

Wireless Gyroscope [on hold]

I doing this project where i require the use of an analog gyroscope that will have to be wirelessly connected. I have been told that I can transmit the signal through a RF transmitter but the output ...
1
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1answer
85 views

How to amplify a very small signal

I am trying to wrap my mind around very small signals; what they mean, and how to amplify them. For example, here is a screenshot from my cell phone. Notice the signal level received is -97dBm. ...
0
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1answer
38 views

ttl 3.3v but almost 0 amps, max232 does not send anything at 12v

Here I have basic board which has ttl serial working on 3.3v (yes I measured it) but it does not have any amps, it barely can light up pore led diode, with my meter it shows 0 micro amps current with ...
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1answer
47 views

Common-Drain Amplifer vs OP-Amp for unity gain (voltage Follower)

What is the difference between using a nFET vs OP-Amp as a unity gain amplifier, i.e. voltage follower. Application: Provide constant voltage with a variable load, see example below: Min Current ...
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1answer
34 views

input of class E amp

i don't want to lose time on understanding it's theory, i just wanna know what kind of input does it take in, does it take a PWM input like the class D (the one below) ? or just a ON/OFF signal ...
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1answer
38 views

Wireless amplifier antenna

There is something like an antenna that works like an amplifier, repeating every signal in the device frequency operation range but wireless. I mean that this "dumb" active antenna receive every ...
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1answer
46 views

Is this a class A type audio amplifier circuit?

please find the amplifier ckt attachment with this.i got this ckt from your page. can you please tell me, this is class A type audio amplifier ckt? i want to make this amp. and what is the power ...
0
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1answer
41 views

Problem Measuring Current in a High Voltage circuit with arduino

I 'm measuring a current in a resistor as shown in the picture below. There I'm using a voltage substractor with an LM324 Operational Amplifier. I'm having trouble in the real World when the voltage ...
0
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2answers
63 views

Need simple audio amplifier

I'm more of a programmer then a circuit designer (read: I'm not good with EE stuffs at all) but I'm working on an arduino project and it's not loud enough. I was trying to drive a piezo buzzer to make ...
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0answers
40 views

Gain in common source amplifier

Let us consider the Common Source amplifier depicted below: We know that the gain \$A_v\$ of a such circuit is given by \$A_v=-g_mR_D\$, where \$g_m\$ is the transconductance of the MOSFET. We also ...
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0answers
99 views

Buy amplifier to amplify analog 0-5V signal to 0-10V [closed]

I realise the title question has already been answered here in one way or another: Amplify 0 - 3.3V DAC signal to 0 - 10V and Scale 30-50mv signal to 0-5v range I don't understand electronics very ...
2
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0answers
60 views

60 dB gain at 20 MHz

I am designing an IF amplifier circuit that needs roughly 60 dB of gain at 20 MHz. I was considering a cascade of 3 x 20 dB MMIC gain blocks but I am wondering if there is a better way? The ...
0
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1answer
35 views

Differences between preamplifier, instrumentation amplifier and LNA

I am confused about the definitions of these amplifiers. It seems LNA is used for RF frequency band but I also see people using INA's for receiver. Why LNA's need careful impedance matching but INAs ...
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2answers
52 views

Why do we short the input when calculating the output impedance?

I believe the title says everything about the question. My issue has to to do with the following: Consider a two-port given by: $$V_1 = Z_{11}I_1 + Z_{12}I_2$$ $$V_2 = Z_{21}I_1 + Z_{22}I_2$$ Cleary ...
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1answer
33 views

Stereo volume control in headphone amplifier

I have a headphone amplifier schematic and I want to make it in stereo. My questions are: Is there any way to realize the volume control with one potentiometer, or should I use some kind of dual ...
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1answer
38 views

Does a BJT Class A Amplifier act in Reverse Mode?

The signal above has negative voltage, so should I take it that it is positively clamped or biased? Or, does the NPN go in Reverse Mode, which I don't think it does (as Reverse Mode only explains ...
6
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1answer
498 views

How does this BJT transistor circuit works?

I just wanted to know a little more about this circuit about how it works a more in depth analysis I mean. I know there's some kind of differential amplifier and a Zener diode for voltage regulation ...
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0answers
66 views

0-1 V input to 0-5 V Output [migrated]

We have an instrument that has analog output of 0-1 volts and we need to convert this to 0-5 volts. What is the best op amp to use for this and how should the resistors be set up? Any help would be ...
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0answers
28 views

Amplifier chip overheats without input; how do I determine whether the problem is internal or external?

I'm building a boombox around a Lepai LP-808 amplifier, which seems to be a thin wrapper around the Sanyo LA4636 chip (with some treble and bass adjustment added). The chip has begun overheating ...
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1answer
106 views

Problem understanding the operations of capacitor

So far I've learnt about some different types of capacitor arrangements , such as coupling , decoupling , bypass , filtering , and smoothing capacitor. Decoupling and bypass capacitors are the same ...
0
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1answer
83 views

How do I amplify an input signal to match the peak of another signal

I would like to build building a Voltage Controlled Oscillator (VCO) for audio applications beginning with a relaxation oscillator build from op amps. Adding a potentiometer to the feedback loop ...
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1answer
50 views

Power supply issue with LM384 audio amp

I made an audio amp using the LM384 : My soldering skills aren't great but eventually the circuit itself doesn't look too bad. To power it, I used an old laptop power supply (18.5VDC - the datasheet ...
4
votes
2answers
123 views

Amplifying a high frequency signal of 30 Mhz or above using OpAmps

I am testing a 34 Mhz amplifier in an inverting configuration with a gain of 20. The cutt-off freqeuncy of amplification stops almost at 15 Mhz , which is very low. I want it to continue up to 27 ...
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1answer
32 views

Phase Invterter Circuit

I am using a current to voltage converter (I-V) to convert the current in the form of sine waves from an electrochemical cell (working electrode) into a voltage. I am using op-amp TLE2062 from Texas ...
2
votes
1answer
88 views

LM324 Difference / Instrmentation Amp 1mV Signals

I need to amplify 1mV signal from a wheatstone bridge (no DS available). 5kg max weight; output is 1mV/Kg @ 5V. The resistances are 880+880 and 749+749. Currently I only have LM324 and LM358. And ...
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0answers
338 views

The Op-Amps don't work correctly for this circuit [Thermocouple]

I'm trying to connect a thermocouple to an Op-Amp to amplify the output of a thermocouple. this is the circuit: Also for R17 I put a 5k09 resistor instead of 6k8 and for R18, 1k032 and for R19, ...
2
votes
1answer
71 views

Arduino Uno - Analogue Signal Conversion Issues

The output of my Low Noise amplifier is a rough sinewave with a peak-to-peak of 1.7V and is shown in the oscilloscope trace below. I would like to use one of the analog pins on the Uno to perform ...
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3answers
96 views

Why signal is inverted in common emitter amplifier?

Why signal is inverted in a common emitter amplifier?
0
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1answer
200 views

What does this schematic of an Op-Amp and Capacitor mean?

I'm still learning about electronics and electricity. But I'm puzzled by this question from a past exam. I'm not sure if any voltage is getting across the capacitor, since Vin and 3v are seperated ...
1
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1answer
37 views

Push-pull Amplifier Class AB

I am new to electronics and I am trying to build an audio amplifier with an input signal of 100mV @ 60 hz using 12V as VCC and expect an output of 70-75W power. I have the following circuit: I ...
0
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1answer
44 views

How does one calculate the input impedance of a tube based preamp?

I'm finding tons of information and equations on calculating this for solid state devices, but nothing for good old fashion particle accelerator based amplifiers :P Currently I'm revamping the K270 ...
0
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2answers
100 views

How to set up load sensor in a full bridge with amplifier?

I I'm somewhat new to electronics so forgive me for what I don't know. I'm learning as I go along here. The overall project is I'm trying to make a scale connected to an arduino board that will ...
0
votes
1answer
25 views

Match impedance and net dimensions of RF power amplifier

this could sound a repeated answer but to me it seems to be not so trivial. Or at least, it is so due to my ignorance. I need to use an RF6886 power amplifier to interface it with a 50 ohm antenna. ...
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0answers
30 views

voice frecuency filter

im building a circuit, it must take a audio recording, of somebody speaking on the street or something like that , or it could be also someone speaking with some noise next to him , and the idea is ...
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votes
0answers
44 views

Adjusting ground level to 1.5 volts for LM386 audio amplifier

I am attemting to use an STM32F4 Discovery to play music through LM386 amplifier. I have tested the LM386 circuit with a spliced headphone and mp3 as input and now attempting to play the music off one ...
0
votes
0answers
27 views

How to continue my solution differential amplifier?

A differential amplifier is fed in a balanced way with the source resistance Rs which is in series with each base.Show that a mismatch ΔRs between the values of the resistances of the source brings a ...
0
votes
1answer
49 views

Need a voltage follower buffer for a tube, how do I calculate and select a mosfet?

I'm finishing up a design here: https://123d.circuits.io/circuits/852190-jan-6418-vaccum-tube-valve-preamp which is a preamp for an instrument. First, let me know if anything stupid pops out at you ...
0
votes
1answer
28 views

Where would be the best spot to put a logarithmic volume control on this TPA3122 audio amp?

I'd like to add a volume control to the following circuit (a 2x15W Class-D Stereo Power Amp Kit). The schematic below is an image clipped from a PDF I found describing it. This'll be being driven ...
0
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2answers
90 views

Class A single transistor amplifier with 2N3904

I made a simple little transistor amplifier using the 2N3904 (basic class A amplifier): \begin{align*} R_1 &= 2.2\, k\Omega \\ R_2 &= 1\, k\Omega \\ R_L &= 22\, \Omega \\ R_E &= ...
0
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3answers
46 views

Non Inverting Summing Amplifier - Ripple Gain

I've created the following non-inverting summing amp. This seems to sum flat DC fine although if I add ripple, the ripple get amplified, surely this should only add the ripple. Why is the ripple ...
0
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1answer
30 views

MOS amplifiers CMRR question

As we know ,in MOS differential amplifiers we have Rd mismatch and gm mismatch.These mismatches have effects on the differential amplifier.Which of the effects of these mismatches is more dominant in ...
0
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2answers
72 views

Microphone amp getting only 1x gain?

I'm trying to build Sparkfun's sound sensor and testing the first stage only. Here's the first stage: If I scope before C2 and at Pin 1, I get the following when I scream at it: where Ch1 is the ...