Tagged Questions

Simply the ratio of output signal to input signal, this dimensionless quantity is a measure of the amplification of a signal which may be represented by voltage, current of may even have a digital representation. A very general concept sometimes used to describe attenuation (when gain

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0answers
16 views

A closed form for calculating shaping gain

As we know, in a communication system, we can divide the overall gain into coding gain and shaping gain, but I have not seen any closed form formula for calculating shaping gain, but the definition ...
0
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2answers
55 views

Amplifier gain too HIGH?

I have this circuit : Two common base amplifiers for amplifying frequency in FM range (88 to 108 Mhz). The Problem is, as seen in the figure, I am getting an output of 1.5 V for an input of 10 uV. ...
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2answers
75 views

Is possible to use wave guide to decrease beam width?

If I use a normal 1/4 monopole antenna "30 MHz for example" and cover it with metallic wave guide has a narrow beam width, should the gain increasing according to this formula below? $$G = 10 \; log ...
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0answers
34 views

Is possible to get very narrow beamwidth antenna?

Is possible to make 60 dBi sector or patch antenna by make its beam width 0.17°/0.17° only ? how to calculate ideal dimensions against frequency at this range of beam width ?
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3answers
67 views

Calculating gain of multiple antenna system

Some radars have thousands of antennas, there are also some routers that have multiple antenna systems. But I want to know how to calculate total gain of multiple antennas in a system? Is it simply ...
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1answer
81 views

Just I want to understand gain, power, link budget

I am a beginner, I am confused about calculating the nessecary gain and power and sensitvity to overcome path loss at certain distances. the first thing what does gain mean ? I am not talkink ...
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1answer
51 views

If I connected N numbers of amplifiers each have X gain 'dB“ and Y power ”dBm", how to calculate total gain and power?

sorry for bad description, I am a beginner. my question is just for knowledge and I did not test anything. If I connect for example 3 amplifier , each one has 60 dB gain and 15 dBm power. can we ...
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2answers
52 views

Prevent loss of Large Signal Voltage Gain at low Rload

Operational Amplifiers (opamps) have the tendency to drop their Large Signal Voltage Gain when the load is too low. This behaviour is usually described in the datasheet. Loads of 500 ohm and lower ...
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3answers
286 views

Why is an op amp's bandwidth higher at lower gains?

If I build a resistor network where the op amp has a lower gain, it is able to maintain its gain for a larger bandwidth. Why?
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1answer
69 views

Op-amp and manipulating its linear output range

First of all let me give some background on the problem. I'm not a native English speaker and I have a basic understanding of amplifiers and op-amps. I am having trouble with one problem in English ...
1
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3answers
91 views

Effect of non-inverting op amp on the AC and DC components of the input

I was wondering what the effect of an op amp like the one in the image below is for an input signal such as \$0.5\sin(2000\pi t) + 0.5\$ V? Are the DC and AC components amplified with the same gain? ...
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1answer
83 views

Gain bandwidth product of op-amps

What is the gain bandwidth product of an amplifier? (What does it mean?) How can I find the gain bandwidth product for an amplifier which has a gain of -100?
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2answers
78 views

How to achieve large gain in the transfer function with OP-AMPs?

My transfer function is: $$ \frac{-115.298}{1+5\centerdot10^{-4}s}$$ To achieve the denominator I used an inverting op-amp with Rf = 1k, Cf = 0.5uF (ceramic, and both in parallel) in feedback and R ...
1
vote
1answer
73 views

What is the current gain of this op-amp circuit?

I just happened to see this circuit in some lecture slides and I thought I could solve it. Unfortunately, I've been trying to check my result with an ideal simulation in LTspice and all my attempts ...
7
votes
2answers
294 views

Common Emitter not amplifying

I am trying to make a 27 MHz carrier wave transmitter from a crystal oscillator and a secondary amplifier. Thi is the complete circuit: simulate this circuit – Schematic created using ...
3
votes
1answer
89 views

What exactly is (Horn) Antenna Gain

I was doing an experiment for finding the radiation pattern of Pyramidal Horn Antennas at RF frequencies(as part of my course curriculum). There I came across the Friis Transmission Equation What ...
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2answers
101 views

Op amps with 1000 gain and 10 volt out

I've been looking for a part that I can boost a 10 mV signal to a 10 volt signal using a single op amp, so far most of the op amps I've found only meet the gain requirements, but cannot output 10 ...
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3answers
159 views

Amplifier design: feedback with unclear poles

When designing a closed loop amplifier for audio the poles of the open-loop transfer function are usually only vaguely known. \$\frac{1}{(s-p_1)(s-p_2)...}\$ These poles can be modeled as \$RC\$ ...
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1answer
101 views

Modeling diode connected transistor in differential amplifier

I have question about the analysis of common-mode gain of BTJ differential amplifier with active load on the Sedra Smith book. In this book, the differential-mode gain \$Ad\$ is derived based on the ...
2
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1answer
85 views

Op Amp magnitude of gain proof

I've been working through a proof but I'm stuck on one of the last steps. Consider an inverting op amp with a feedback resistor \$R_f\$ in series with a capacitor and resistor \$R_1\$ simulate ...
2
votes
1answer
63 views

When the Gain Margin is negative, for what range of frequencies is will the output resonate out of control?

If your system/transfer function has greater than zero gain for the frequency associated with -180 degrees phase, the system is said to be unstable. What does this mean for other input frequencies? ...
2
votes
2answers
91 views

OpAmp configuration with gain less than 1

The output voltage from AD5611 DAC is rail-to-rail, and minimum Vcc is 2.7V - therefore, the signal range is 0-2.7V. I need to attenuate this signal to let's say 0-2V range. The DAC output is very ...
1
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1answer
94 views

High-gain feedback amplifier design using ADA4004

I am trying to design a feedback amplifier with ADA4004. My desired gain is about 42dB@2kHz. Is it possible to design a stable amplifier with such gain using ADA4004? The ADA4004`s GBP is 12MHz. The ...
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votes
3answers
162 views

BJT amplifier gain rolloff

I'm playing around with BJT amplifiers and have some questions regarding the gain rolloff you see at higher frequencies, I'm using the 2N2222 for my tests and my simulations and measured results match ...
0
votes
1answer
72 views

Mosfet gate resistor vs Gain

I have a small question. I was doing a lab with MOSFET 2N7000. The circuit is something like the one below: There was a question asking if the gain should change if the resistor R1 was changed to ...
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4answers
253 views

Controlling an Op-amp gain using an MCU && || DAC?

I'm building a circuit that will generate various wave forms. The output from the circuit is fed to a summing amplified where positive or negative dc offset is being added. This signal should be ...
1
vote
2answers
267 views

I'm confused by the formulas for power gain decibels and voltage gain decibels [duplicate]

I know that my problem with this is some flaw in my logic, I just need someone to point out to me where that flaw is. According to the Wikipedia article, there are different formulas because power ...
2
votes
5answers
129 views

Given an Op Amp where the output voltage is fed back into the negative terminal, why is the gain one? [duplicate]

Apparently, the gain of this Op Amp is one, but I can't see how I could figure that out. Can someone help?
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2answers
91 views

Gain of a circiut

I have been asked this question: Identify the gain of the sensor circuit. If the gain is \$\dfrac{V_{out}}{V_{in}}\$, then won't the gain be dependent of the thermometer's resistance? At 0°C, ...
0
votes
3answers
185 views

High-Gain Common Emitter Circuit

I am trying to design a high-gain common emitter circuit. I know that I need to use a bypass capacitor with emitter resistor to increase the gain. My problem is the formula A = Rc / re makes things ...
-1
votes
2answers
178 views

What is the difference between Rf Gain Blocks & IF Gain Blocks?

As advertised on websites of large manufacturers like Analog Devices And Texas Instruments I am aware of the difference between an IF stage and an RF stage, however, I was curious if there was any ...
0
votes
2answers
199 views

Is a subwoofers RMS/peak wattage rating subject to the enclosure type?

The RMS and peak wattage rating of a subwoofer (or any speaker) show afaik how much power it can safely handle without damaging it. But is this true for both sealed and ported enclosures? (assuming ...
-4
votes
3answers
699 views

LM358 output voltage non-zero even though input is zero [closed]

I tried this experiment with LM358 and LM741. I used the circuit mentioned from this question: I have not connected any input source. But I am getting an output of 7.5V. I used R1 as 130 Ohm and R2 ...
0
votes
0answers
60 views

Circuit to fix the amplitude of the sine wave

Does anyone have any idea on how to stabilize the various input amplitude of the sine wave for example 1.3V,0.8V to 1V of frequencies between 0 to 10Mhz? I known that a variable gain amplifier can ...
1
vote
1answer
124 views

How are the gain and corner frequencies calculated for this speech bandpass filter?

This speech bandpass filter circuit appears in the TI OPA344 datasheet. It says "G = 100" and passband is 300 Hz to 3 kHz. How is the gain and corner frequencies calculated from the various ...
8
votes
4answers
3k views

Choosing resistor values for non-inverting amplifier and why?

The gain here is A = -Rf/Rin. However, lets say I want a gain of 10 V/V. Which resistor value would you choose and why? I know that you could have infinite number of combinations for these ...
1
vote
1answer
129 views

Gain of this schematic

I am interested in the following compressor, which I reverse-engineered from a pcb (there might be some mistakes, but I don't think so) (open the schematic in a separate window to see the small ...
1
vote
2answers
90 views

How important is the temperature stability for gain - setting resistors?

When two resistors are used to set a gain of an opamp, do I need to care about their temperature stability, provided resistors are from the same series, same manufacturer? Let's say my circuit will ...
3
votes
2answers
303 views

Problem with Wien's Bridge basic working and simulation in multisim

I am very new to the concept of Wien's bridge and am trying to make a basic circuit of it but didnt get the expected output (noise only).Tried to simulate on Multisim but got the same output.I have ...
4
votes
2answers
119 views

How to know the gain of my opAmp

I'm having a LM358 opAmp with the following Schematic, as I'm not from Electrical background, can you please help me determining it's gain. I just want to find out it's gain. simulate this ...
3
votes
2answers
132 views

How is the gain/phase vs frequency measured for opamps?

Opamp manufacturers post graphs like these in datasheets: How is the data for this graph measured? Is it calculated using the mathematical model of an opamp?
1
vote
0answers
48 views

Are RF gain blocks suitable for making VHF oscillators? [closed]

E.g., can I use them in circuits as active filters with positive feedback to generate VHF? Can't find models to simulate them. Is it possible to obtain them somewhere? The model I'm particularly ...
2
votes
2answers
378 views

Gain in Common Emitter Amplifier

I need to design an amplifier having a Vin=150mVp, 1khz; Vcc=3V that can run an 8ohms, 0.25 watts speaker, with a gain for about 7 without noticeable distortion. Below is my designed voltage divider ...
2
votes
2answers
327 views

How does the fuzz face guitar pedal actually output any gain to the input signal?

I'm referring this this circuit right here: I do not understand why the circuit would be designed like this and why the output wouldn't be drawn from the collector of Q2. I have 2 questions, which ...
2
votes
2answers
2k views

Op Amp gain less than 1?

How would I design an op amp with a gain of less than 1? Is this even possible? Also would it matter if I used a non inverting or an inverting op amp? I've designed a non-inverting op amp with a ...
0
votes
1answer
98 views

Calculating gain, input and output resistances of a current amplifier circuit

In the circuit below, I want to calculate the gain, $$\frac{I_{out}}{I_{in}}$$ as well as the input and output resistances. I wrote the node equations for the two nodes: $$V_x ...
1
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2answers
160 views

Advice for my Voltage controlled Amplifier

In class we are designing a VCA together as part of a bigger circuit. The aim is that we have an input of speech and an input of music and when we speak the the music reduces in volume. The speech ...
1
vote
1answer
115 views

(Ideal) Amplifier networks/nullors - determining the gain

I am having trouble understanding how the different amplifier networks actually do "their magic". In these networks a nullor is a unite that has always 0 voltage over the input and no current through ...
0
votes
1answer
52 views

How to find the gain of Motorola operational amplifier?

How to find the Gain in dB for Motorola operational amplifier MC33282P (for T=25°C). The manual has only abstract figures.
2
votes
1answer
262 views

Distortion in the output of amplifier circuit using uA741 + schematics and graphs

I'm simulating an audio amplifier with uA741 in pspice (student version). The input signal is a 0.1v (100mv) sine wave with frequency between 1kHz and 10kHz. The theoretical gain is 33 but in ...