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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generating a 10mVpp signal from computer

I have an input to a system that requires a 10mVpp max signal. I have to use my computer to input it due to constraints out of my control. I am well aware an audio card cannot go down that low. I ...
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37 views

How to calculate transmission capacity of a channel?

So I have the following question: "If a transmission channel uses an analog carrier wave that is modulated by eight amplitudes and sixteen frequencies per bit time, then what is the transmission ...
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1answer
57 views

Noise can be Differential or Common!

I have a basic understanding on this topic but i still have some doubts, my text books says Differential means it will have impact on one of the 2 signal nodes. and Common will have a common impact on ...
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0answers
22 views

Help with drawing small signal circuit model

I am working on a small question regarding small signal circuit. All mosfets are in saturation. I drawn a small signal model myself as below: If connect node Y to node V(Y) so as to link them ...
7
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7answers
915 views

Why is one return conductor for each forward conductor in a ribbon cable better than a shared return conductor?

I don't understand why second way of implementing is better than the first one? I have my own basic logic regarding this topic, but i am not confident if what i think is correct! so i was looking ...
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1answer
29 views

How to evaluate quality of signal?

guys. I'm trying to evalute received signals from a transceiver. I'm a rookie in wireless communication. So I hope that you guys can help me out. I want to make a threshold of received signal so that ...
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2answers
34 views

Band-pass filter with a given impulse response (Matlab)

I am trying to pass a .wav sound waveform through a band pass filter whose impulse response is given by \$ h(t)=50u(t) \exp(-10t) \sin(2 \pi 440t), \$ I have imported the file into Matlab as ...
7
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3answers
541 views

Chokes vs. small capacitors on signal cables

I know that many signal cables (usb camera to computer cables, etc.) have bulky ferrite chokes on them to prevent noise. Why do they all have ferrites instead of ceramic capacitors? Small ceramics ...
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0answers
33 views

how to sample and modulate a gps gold code

I am trying to simulate the data transmission of a GPS satellite. Telecommunications is not my field so I am struggling a bit with some concepts. I managed to generate the Gold code of the GPS ...
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2answers
52 views

Fourier Series Coefficients Calculation

Could someone tell me where my calculation is going wrong? So I integrate $$\int_{-1}^1te^{-jn \pi\ t}\ dt$$ and get $$\frac{e^{-jn \pi\ }}{-jn \pi\ }\text{+}\frac{e^{-jn \pi\ }}{-(jn \pi\ ...
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1answer
52 views

\$e^{i2\pi Nf_snT}=1\$ why?

Why is: \$e^{i2\pi Nf_snT}=1\$ in snippet from book
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1answer
48 views

Is it possible to measure Spinal Cord electrical activity over skin? [closed]

sorry if this is not the right place to ask this question. I'd like to know the possibility and reliability of measuring electrical activity of spinal cord (specially the cervical region) if it's ...
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0answers
9 views

How to improve wifi coverage when my router needs to be in an awkward place? [migrated]

I live in a 1100 sq ft (100m²) apartment. I receive internet via an ethernet cable in a small space inside one of the bedrooms, far from the living room and the master bedroom. The router sits in that ...
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0answers
25 views

difference between rising and falling time from the pulse response of transmission line

Attached is output pulse response of a transmission line (s-parameter). In the high-speed serial link design, we usually see more # of post-cursur ISI than pre-cursor ISI. One of the main reason is ...
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2answers
66 views

On board signal termination

and thanks for bothering with my problem. I have a two signals A and B that I want to route using several alternative paths via jumpers on my board. In one of the occasions I need to use the same ...
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0answers
36 views

complex signals and modulated signals [duplicate]

I'm taking an intro electrical engineering class in an online university and have come across something that is confusing, at least to me, since the text we are using does not go into detail about ...
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0answers
30 views

What is the absolute phase and the relative phase, of a signal?

I need to know what is the absolute phase and the relative phase, of a signal? and why these phases are important in the signal processing?
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1answer
47 views

How frequency generator in telephone works

I was doing some research, on how telephone works, and I found that when user, click numbers they are converted to frequency and passed to wire. I want to know how the frequency generator work, what ...
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2answers
84 views

Ambilight without computer - µC [closed]

Firstly, sorry for my english. I'm not very confident with this language but i'll try to give my best for you guys :). So, now i will talk about my main problem. For my school project, i have to ...
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4answers
113 views

What analog circuit i should use to shifting a signal from -5..5v into 0..10v? [duplicate]

I want to output my circuit from -5..5v into 0..10v. My circuit generate -5..5v. What should i do to generate that signal? what analog circuit i should use? thanks
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1answer
27 views

Some confusion about differential-ended data acquisition system

I have many transducers which all have single-ended signal outputs. I hook them up to a single-ended DAQ board. A board with 16 single-ended inputs. The DAQ bard is currently set to single-ended ...
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0answers
31 views

Low Frequency signal detector with MOSFETs

Does anyone have any ideas on creating a very basic signal detector (low frequency is fine) with MOSFETs? trying to design a small profile detector. My idea was to use a basic field strength meter, ...
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2answers
55 views

Copying/imitating wireless garage opener radio signal

I aim to be able to copy my garage door opener onto another device, but for that to be doable I first have to be able to recreate the radio signal that is sent from the garage opener. Is there any ...
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0answers
11 views

measuring the coherence between wearable sensors signals

I am trying to measure the coherence between two acceleration signals collected from two different wearable devices, smartphone and smartwatch, I am applying the Coherence (signal processing) and I ...
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3answers
55 views

Emulate the effect of a lock-in amplifier on a signal with a programming script

I'm working on a gas emission sensing project in the lab which requires the extraction of a signal in a really noisy environment. The features of interests of my signal are much smaller than the noise ...
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2answers
76 views

Arduino signal conditioning

I'm doing a project with an Arduino. I read a voltage from a tachometer connected to a generator. The nominal max output is 21V at 1000 rpm. The generator is managed so that the maximum tachometer ...
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1answer
44 views

vhdl - convert a signal to integer

I have looked around on SE but couldn t find anything that worked properly for me. I am looking for a way to convert a 4 bit signal_vector to an integer. However I do calculations on signals as well. ...
0
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1answer
58 views

Do wireless amplifiers work in both directions?

I'm especially wondering about wifi aplifiers (2.4GHz and 5GHz). I have a couple of very basic questions about them. (I hope this is not too much for a single question): Are there special signal ...
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0answers
24 views

Bandwidth difference between a transmission medium and a given signal

What's the main difference between the bandwidth of a transmission medium and a given signal? Don't they both follow the same formula, i.e. Bandwidth = highest frequency - lowest frequency?
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2answers
53 views

Steady State Error: why we use a negative feedback rather than a single gain to reduce the error?

I'm studying signal analysis, and we reached a topic of correcting and enhancing a system with the following transfer function : $$ \frac{Y(s)}{U(s)} = \frac{2}{s^2 + 5s + 6} $$ with \$U(s) = ...
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1answer
42 views

Digital Signal processing-Sampled period

Please can you help me with exam test preparation. I have take the below past year exam paper. I want to know if I am on the correct track and my answers are correct. x(t) = cos(50.pi.t + 30) ...
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1answer
96 views

Help determining power and energy of various signals [closed]

I need a bit of help. My problem is to determine the energy and power of each of the following signals: ...
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1answer
93 views

What is the FM threshold effect?

I came across a picture ( shown below ) comparing the SNRs of FM and AM. There was also some explanation of the FM threshold effect and how the threshold effect is the reason as to why the FM graphs ...
0
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1answer
43 views

External ADC and FIFO

I have a Micro-controller with ADC input range 0V to 3.6V(12 bit). I need to measure a voltage signal in the range of -10V to +10V. So i chose the option of using an external ADC instead of the ...
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105 views

Can someone help me find the defect on my triangular signal?

I want ask for help. On my final project, I need to generate a triangle signal (I must build it from an analog circuit). As I built the circuit on Proteus, it generates a smooth triangle signal with a ...
0
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2answers
77 views

signal conditioning 0 to (-40) volt to 0-5 volt, arduino

I want to convert my 0 to (-40 )v signal to be 0-5 volt so that i can measure it using arduino, i want to attenuate the signal first by the factor of 8 and then shift it up by the arduino 5 volt. ...
3
votes
2answers
102 views

Trouble with Schimtt trigger settings for varying sinusoidal inputs

To make my problem easier to describe, I drew the above figures (abbreviated as Fig.). The sinusoidal input comes from a rotating device, from a small alternator(a permanent magnet AC generator). ...
3
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1answer
99 views

Alarm sound signal arduino

My vehicle alarm consists of a control box containing some vibration sensor and relays, and a buzzer that creates an ear piercing sound upon triggering. I've recorded this alarm sound. After pulling ...
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0answers
37 views

Signal generator showing an atypical noise power spectral density

As an orientation exercise in the new lab I have started working in, I was tasked with characterizing the phase noise spectrum of some of the signal generators present in the lab. Doing so made me use ...
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1answer
60 views

multiplication of a periodic signal by rectangular pulse

Here is the shape of rectangular pulse and sin(pi*t) in time domain I am trying to sketch this signal, but I kind of don't fully understand the concept. since the two signal are multiplied in ...
4
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1answer
77 views

Phase noise measurement with IQ mixer

I have a question regarding a measurement scheme of phase noise that I'm trying to implement. The idea is that I have two identical signal generators (I actually do) that generate a sinusoidal voltage ...
0
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1answer
56 views

Signal in the wire of headphones

Normally what kind of signal flows through the wire connecting the headphone jacket and the headphone? I wonder whether there is a standard regulating them. And what wavelength, volts, watts, amps, ...
0
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2answers
130 views

Fourier transform of \$x(t) =t^2e^{-|t|}\$

I have to find the Fourier transform of this function. (- sign exists BEFORE modulus). I thought of using this standard result. If I split this fourier transform into this will it be correct ...
0
votes
1answer
50 views

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) ...
0
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1answer
40 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 ...
0
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3answers
55 views

insertion losses [closed]

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 ...
0
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0answers
16 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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0answers
21 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
794 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 ...
0
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3answers
188 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 ?