A signal is a stream of information in the form of a varying quantity. Usually in electronics, signals can be in the form of voltages, currents, or radiated electromagnetic fields.

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Multi-channel high frequency signal acquisition

I have to design a test bench for a device that has more than 1000 outputs. The voltage of these outputs will be about 10mV peak-to-peak, the frequency will be in the range of 100MHz (for the carrier) ...
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25 views

Network signal propagation signal [on hold]

The propagation of signal starts at -15v how low could the voltage get before it is not able to read the message??
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28 views

Network signal propagation [on hold]

In network signal propagation: If 15 volts = binary 1, and 0 volts = binary 0, to what voltage can the signal drop before it is not readable as a 1 by network equipment?
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21 views

the best book to practice [closed]

I am looking for a book that would let me practice the chapters of Principles of Measurement systems by John P Bentley. I am looking for a book that has all the contents of the this above mentioned ...
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1answer
32 views

The relation between a link speed and Fourier coefficients

I am reading Computer Networks by Tanenbaum and the the chapter about the physical link and there is an example that I don't understand. The author states that given a bit rate of b bits/sec the ...
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20 views

More traffic decreases the signal strength [closed]

Why the higher/more traffic that travels through the Access point, will decrease the signal strength of the access point? is there any invers relationships between them ? what is the theory ?
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3answers
51 views

insertion losses

I know that attenuation doesn't change with frequency of signal. However, during my experiment, I found that there is a slight decrease in amplitude of signal when frequency is increased. Can anyone ...
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26 views

Can a SIM number be identified using the phone signal? [closed]

when a call is made can the number of the caller be identified using the signal by anyone ?
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12 views

Driving LRA actuator with a driver

I'm using a driver DRV2605L to drive a LRA from the link below. https://catalog.precisionmicrodrives.com/order-parts/product/c10-100-10mm-linear-resonant-actuator-4mm-type The problem is that the ...
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3 views

how to connect multiple power speaker by using splitter [migrated]

I have 5 self power speakers.. I want to connect this speakers to my computer by using 3.5mm audio jack splitter...is this possible ? does it make any effect on audio single or sound quality? and ...
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0answers
19 views

Finding the expansion coefficients of a waveform

I'm reading the book "Introduction to Electromagnetic Compatibility" by CR Paul, and in Chapter 3, it talks about how to find the expansion coefficients of periodic signals, \$c_0\$ and \$c_n\$. ...
7
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4answers
676 views

What is the difference in meaning of a voltage signal and current signal?

This might sound like a crazy bad question. But I'm wondering even though current and voltage inevitability co-exist, why do we use the term for one concept(current or voltage)? If there is a signal ...
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3answers
90 views

why is noise always a high frequency signal ? what then is frequency of a noise?

while designing signal conditioning circuits for sensors , we design low pass filters to remove high frequency noise. why can't noise be a low frequency signal or what will its frequency be ?
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1answer
60 views

Anolog signal amplification with single supply

I have to amplify an analog signal 0 - 0.3v from a sensor to 0 - 2.5v which the XBee's analog input accepts and onlt have access to one 3.3v and gnd power supply rail(no negative rail). I've tried the ...
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3answers
471 views

Designing op amp circuit that has the following signal at the output

I tried combining several inverters, one summation op amp and one op amp for integration. However, LT-spice produced rubbish at the output, and was really having a tough time doing ac analysis on ...
3
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3answers
251 views

How fast can a Transistor Switch?

An NPN Transistor can be made a switch by applying some power to the Base. Is there a limit to how fast I can switch the Transistor On and Off? Or I can switch it on and off as fast as i can turn the ...
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3answers
91 views

What is the difference between Ground and Low?

What is the basic difference between sending a LOW signal vs GND to a circuit? What If I ground instead of sending LOW? Or similarly what is the difference between Vcc and HIGH?
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1answer
103 views

electronic interference generated by blood? [closed]

Hi so i made a little electrical signal detector that can detect electrical interference/noise(for example putting it near a light or plug makes it squeal). I was messing around with it and noticed it ...
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4answers
58 views

Summing amplifier with bypass

I am trying to sum three audio signals using a non-inverting summing amplifier as shown below. If I want to bypass one of those signals, what is the correct way of doing that (let's say with a ...
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1answer
64 views

Startled by a notation of operator for combining two signals

I am studying electronics and when practising, I got stuck at this simple problem of summing two signals. I believe I know how to work out everything except the combination of the two signals with two ...
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3answers
122 views

How actually an integral transformation(Fourier and Laplace) works?

After seeing a question on one of the posts I got this confusion in my mind. Here I'm not much interested in just mathematical explanation but I would like to know how a transformation actually turns ...
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2answers
598 views

How does a coaxial aerial cable work?

My family and I managed to break the aerial cable of our TV a few days ago. The cable is of this kind of design: And I believe its called a coaxial cable. Fortunately, someone more practical than ...
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2answers
34 views

HP8116A Function Generator Signal Problem

I'm trying to use a function generator HP 8116A and an oscilloscope Tektronix TDS210. When i connect the probe to trigger output of function generator, i can observe the square wave correctly. ...
0
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1answer
28 views

Power of piecewise defined signal

Here is my task: Periodical signal is given (only one period of signal is shown): Calculate value of voltage K so that average power of this signal equals 1.5W. Power of signal can be calculated ...
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1answer
96 views

555 Input Impedance

I'm building an audio circuit and need a comparator. I've explored using an op amp for this purpose but my TL072 doesn't seem to have a high enough slew rate which resulted in latency. Instead, I've ...
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2answers
84 views

How to Clip The Negative Portion of a Signal?

What is an easy way to remove the negative portion of a signal without distorting the positive side of it?
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2answers
78 views

Simulate Gyroscope through MEMS accelerometer

Is possible to simulate the Gyroscope using Accelerometer values? I would like to make that in Android Context so using MEMS smartphone accelerometer.
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1answer
41 views

Data speed (fps) significantly decreased on USB camera [closed]

I have a 5 meter long inspection camera bought on ebay (here), getting 30 fps @ 640x480. I was measuring the resistance between D+ and D- while connected (DP, DM in the actual image), just for fun, ...
3
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1answer
75 views

Understanding the DTFT

So I am taking a signal processing course in EE and my professor is an Engineer who really likes math however his book which we use for the class falls in the dreadful purgatory of math books in my ...
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1answer
40 views

Minimum TTL 5.0V signal duration

I'm working on a little project in my physics lab. We would like to create a photon coincidence counter. We were thinking to use the Pi GPIO pin to monitor a couple of photo diode which produce a 15ns ...
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1answer
43 views

Fast Fourier Transform (FFT) of power consumption signals

I want to compare two power consumption signals, i.e., how the power consumption varies throughout a day. Now I have two options: Take two raw power signals and compute the Euclidean distance ...
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1answer
64 views

BJT Amplifier has different gain for negative and positive inputs

There were some errors in my old question so I decided to close it and redo it here. I am working on a 3 stage npn bjt amplifier for my circuits class. The first two stages are common emitter stages. ...
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35 views

Converting bipolar sensor inputs to unipolar

I need to convert a bipolar input to unipolar signal, with no gain but 2V offset. I simulated the circuit below and it seems to work fine. I want the circuit to work for any kind of sensor or device ...
0
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2answers
110 views

How to record electrical signal through PC sound card as an audio file?

I am doing some study on the frequency of electrical supply. I need to do the analysis on MATLAB. I want to record the electrical signal as an audio file in my laptop. As I am a beginner working ...
3
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2answers
287 views

Does a carrier wave need to be sinusoidal?

I am trying to AM modulate a song and I have an idea of how I am going to do it, but I need a carrier wave to start with and I've been having trouble creating one with a ceramic resonator because I ...
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3answers
71 views

College Computer/Electrical Engineering Circuits - Modulating Signal DC offset based of modulating index question

Here is an image of the question. I am stuck at part a, which asks to find the DC Offset based of a modulating index of 0.7, or 70%. So essentially, you will transform the maximum and minimum, yes? ...
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1answer
38 views

Circuit for DFT transform? [closed]

In my recent project I need to apply DFT to signal and find it's coefficient values. Can you please suggest any circuit/chip which can perform DFT/FFT transform on analog signals?
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4answers
79 views

AC and DC signals

If a AC+DC signal passes through a junction from where a capacitor is connected to ground and resistor is also connected from the same junction to the ground ,will the voltage measured across resistor ...
0
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1answer
24 views

implications of difference between RMS and mean in rectified and non rectified graphs

I have a project relating to EMG signals and i did a full wave rectification to zero for the graphs before calculating mean and RMS of the graph. My question is, would it make more sense to find the ...
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49 views

Adding Multiple Signals to a DC line

Basically, I want to add multiple sine wave signals to a DC line one by one. Details - 24V DC line powers the Oscillator circuit.Its output is to be added back to the power line as shown. The output ...
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1answer
93 views

Carrier generation at receiver in DSB-SC modulation?

As shown in fig., In this scheme input signal is square and passed through a narrow(high Q) bandpass filter tuned to \$ w_c\$.Finally the ouput comes to be a sinusoid of frequency \$ w_c\$. But to ...
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1answer
97 views

Effect on signal bandwidth due to multiplication?

Recently I came across an statement which says, If signal m(t) has bandwidth B then pow(m(t),n) will have bandwith nB. To prove it mathematically I startted with, Let n=2, y(t)= m(t)xm(t) ...
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70 views

3G - Ideal antenna size and amplifying signal?

I am thinking about building my own portable 3G router box. So that I can finally have 3G in badly covered areas and on trains. The idea is simple: [Laptop, Phone, ...] <-> via wifi <-> ...
0
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1answer
33 views

Power normalisation of a signal

I have two signals, say a and b. Signal a has power of 6 Watt. Signal b is summation of signal a and noise n and has power of 7 Watt. I want to normalize the signal b in a way that its power is equal ...
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1answer
246 views

Does frequency need to be an integer in order for a signal to be periodic?

Please help me understand periodicity. Why can \$T=\frac{1}{3}\$ be periodic but \$T=\frac{1}{\sqrt{3}}\$ be aperiodic? For example: $$\cos(2\pi\times 3\times n) \Rightarrow \mathrm{periodic}$$ ...
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3answers
598 views

General question about analog and digital signals

Newbie alert: I am not an electrical engineer, nor have I ever taken electrical engineering, so please bear with me. Whenever I read about the distinction between digital and analog signals, a ...
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vote
1answer
44 views

Find Power Spectral Density of given signal

I am given a question with very brief notes to study from. The question is this: Now I was wondering, are the following part of the notes relevant at all: Is this the appropriate method to solve ...
0
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1answer
44 views

Johnson noise with amplifier circuit

I need help with this problem. Some numerical answers would also be very helpful.
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1answer
45 views

Derive the Power Spectral Density of output process

Derive the Power Spectral Density of output process. This question is from undergraduate physics course. Please help! I do not even know where to begin!
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60 views

Why is this function not invertible?

Why is the following function NOT invertible? $$y[n] = \frac 1 {x[n-1]^2}$$ A function is invertible if two distinct inputs give two distinct outputs. Is there a quick way to check for ...