Signal Definition and 935 Threads

Hi Everyone, below I've attached an embarrassing drawing of a circuit with switches. Signal enters from the left side at both line. Given that each switch has a 50% chance of being open, what is the probability of signal reaching the end of the circuit(far right)? The answer that I got...

Hi, I am not very good at electronic circuit,, I just want to ask: How to amplify voltage signal resulted by piezoelectric? Since the voltage resulted by this material is very small,, thank you for any help

Homework Statement I am trying to construct a Mathematica notebook that will be able to import sound in the form of a .wmv file and then create the frequency spectrum for a given time interval. Homework Equations I managed to complete this part, though I am trying to figure out: a)...

A singal x(t) is bandlimited to B Hz. Show that that the signal x^{n}(t) is bandlimited to nB Hz. I have no idee on how to adress this problem. Can get some help?

Refer to the delayed choice quantum eraser (DCQE) ...for example the kim paper http://en.wikipedia.org/wiki/Delayed_choice_quantum_eraser" i have a few questions, to understand this better, 1. Once the signal photon has been detected at D0, can the path of idler photon be...

I believe its possbile but wanted to ask if its possible to light a single LED light by and RF signal if its strong enough. I know there are LED's that are as low as 3 milliwatt that could work. Thanks in advance.

Dear all I am slightly confused over the definitions of digital and analogue signals. Is a digital signal discrete in time AND voltage or just discrete in voltage. For example, could a square wave that is continuous in time, but has discrete voltage levels be considered a digital signal...

Dear Experts, I am looking for some rf vhf diodes. could you recommend a particular model for me? I am quite new to this diode. Are these synonymously called microwave diode / MOSFET / rectifiers / field effect transistor? I am confused what should be the right diode to amplify gsm...

Hello , I'm working on a project where I'm using a wii remote to track an infra red LED. The wii remote is connected to the computer via bluetooth. I've no experience with dealing with the wii before. My questions are: 1- How can I read the data send by the wii remote to the computer ...

I have a sinusoidal AC voltage with roughly Vrms = 50mV. I wanted to amplify with a non-inverting amplifier circuit with the LM358 op-amp. I used resistors of 100ohm and 10kohm for a theoretical gain of 100x. However, my output signal is rectified so that only the positive half of the signal...

I am looking for ideas on how to make a motor run for a certain period of time, but I do not have much experience in circuits. The design is to have the system start at the push of a button. The design can be mechanical or electrical. As of now I am wondering if there is a device that will...

hello, this is not a homework question, but i can't understand something, we're currently learning about signals, bandwidth, transfer rate etc, but i don't understand something i can understand that when we talk we create signals with a specific frequency, then this signal travels through...

hello fine people, some days back saw a signal generator. it has buttons labelled as 1hz, 10hhz,1k,2k,5k,etc. it does not has its own display. you can connect it to some external device for display. me do not have access to it now. it had a dial which could be turn with markings 0.5,2.5,0.1...

Hi, How to check my transmitter signal power? I have found my transmitter in my friend shed and needs some new output transistors. But i don't know what is the power of my transmitter and if it worth to repair it. There is the RF board and also a encoder. There is also an amp so i don't know...

Homework Statement given this discrete time signal x[n] = u[n] - u[n-6] find for which n the even part of x is 0The Attempt at a Solution the even part is x' = 1/2(x[n] + x[-n]) = 1/2(u[n] - u[n-6] + u[-n] - u[6-n]) now i find that u[n] + u[-n] is 2 for n = 0 and 1 for n != 0 u[n-6] +...

small signal equivalent circuit model for the HJFET?? hello all, Looking for small signal equivalent circuit model for the HJFET. can someone knows ? Please help me it's urgent... Thank you in advance, N

Hi guys, I am designing an OFDM system and then upconverted at 1 GHz. Now I have an idea of implementing TDM for this 1 GHz signal. Is it possible, please explain from theoretical point of view and if possible, please help from MATLAB perspective. Thank you very much,

To avoid busy waiting...we use block and wakeup functions in our definition of wait() and signal() but its mentioned in Galwin that still we have not been able to eliminate busy waiting completely... "we have just removed busy waiting from entry to the critical section...futhermore we have...

I took the FFT of a signal that was taken at non constant time period (T), but at a sampling frequency(Fs) of 6.5 hz. Can I take the FFT of a signal with non constant T, and does it mean anything? Please see attachment. Ps. I used Matlabs, FFT command, which i think uses the Cooley–Tukey FFT...

Homework Statement Given a sine wave signal (20V PP) connected to a 10 kilo-Ohm resistor. Calculate the current through the resistor in terms of average, rms, and peak currents. What wattage rating should the resistor have? Homework Equations Vrms=(1/Sqrt(2))(Vp) V=IR The Attempt...

I have m(t)=0.2sin(w1*t) + 0.5cos(w2*t) ---> Note: the 1 and 2 besides "w" (omega) is not a coefficient, its a subscript to show that they are different. I found the Fourier transform to be M(F)=0.25[∂(f-f2)+∂(f+f2)] + 0.1j[∂(f+f1)-∂(f-f1)]. My question is, how do I sketch the magnitude...

I have found a circuit that uses a BAS16 small signal diode to level shift a 5V (or 3.3V) TTL signal down to a 1.8V TTL signal. The cathode of the diode is on the high voltage side and the anode is on the low voltage side, so it looks like it is backwards compared to the direction of current...

hi... after amplification of a signal through an amplifier, the amplified signal is 180 degrees out of phase with input..why?? thanks..

Hello everyone! I have a system with 2 lasers and a single camera. I have two trigger inputs going to each laser, they have a delay of minimum 350ms. These triggers are split and need to be connected to the camera to open it whenever the lasers fire. So i thought of a Tee junction where i...

I have the readings from a signal in a file (floating point values) that I wish to apply the Fourier Transform to. The samples (mV) were taken every 4 milliseconds and I wish to transform them into the frequency domain. How would I apply the FT to a set of values without knowing any...

Hello all, I'm an electrical engineering tech student working on a little side project and I can't find anything to help me with a crucial part. I have a gauge cluster out of an automobile that I want to interface with a computer to used while playing a racing game. I have a computer...

While studying the type of signal propogation in telephone wires, I read that it has a bandwidth of 400-3000 Hz and the signal travels with the speed of light(as in case of all electric signals). So electronics at the two ends communicate atonce. One changes the voltage at one end and the other...

Suppose you have a source that send a very strong straight beam of light (say laser ) Then you direct the light toward a distant wall with angle 45 degree as show in the drawing below Then if you rotate the source 90 degree in one second, what is the velocity of the visual effect (spot)on...

I've got a signal coming that can theoretically reach a maximum of 400V and at around 5A. This is not an AC signal, it's DC. However, I need to attenuate this signal down to a maximum of +- 10V. What steps do I need to take? How do I go about this? How to minimize loss of signal clarity?

Hello to everyone :) Since I did not notice a presentation section I put some info about myself before the question,. My name is Enrico, I am Italian (form Modena) and I am 18. I am studying Electronics&Telecommunications in High School and I have applied for UCSD/UCLA/Berkeley (I hope they...

Computationalism has a number of inconsistencies that haven’t logically been refuted. The purpose of this thread is to discuss one of them and see if there’s a way out of the problem and/or to help get perspectives on the problem. That problem I’ll call the “special signal problem”. In the...

Homework Statement Determine whether or not each of the following signals is periodic if signal is periodic determine the fundamental period (note that these are discrete not continuous signals) Show your solutions 1. x(n) = \cos^3(\frac{\pi(n)}{8}) 2. x(n) =...

Hello, Can you suggest me some good Math books about Fourier laplace transforms, convolution, transfert functions and stuff ? Because all I have right now is some crapy math notes and an electricity book that doesn't mention anything about math theory. I tried google but I really don't...

I am trying to get an understanding of what a good signal to noise ratio in terms of decibels. My SNR is roughly 20 dB, and am concerned about being able to resolve the signal from this.

Hi All! I has probe (B-field induction probe) with non linear amplitude-frequency characteristic. I has calibration table with 3 columns: frequency, amplitude, phase. I has output signal U(t) recorded with sample frequency Fs during rather long time. Can I restore input signal (i.e. B-field...

Mathematica problem: Filter: H(jw)=(3.84+5 (j w))/(5+j (1.11 w^2)) Bandwidth where: |H|>1/Sqrt[2]*Hmax Calculate the bandwidht Tips or solution would be much appriciated Thanks

I'm not an engineer and so I appreciate everyone who contributes. 1)Is there any measurable cell phone interference from a car battery, alternator, or starter while the car engine is running if the cell phone is in the driver's seat? 2)What would this interference look like? Thank you.

Hey Guys, Im currently designing a primitive audio mixer unit using opamp circuits for simple filters/crossover networks. Prior to the signal being run through a power amp circuit I am looking to pass the signal to an ATmega328 MCU which has an ADC with a range from 0 to 5 Volts outputting to...

Hello, I'd like to know the relation between the sampling frequency and the quantization. If the sampling frequency is 200KHz, and the analog signal ahs a maximum frequency of 80KHz, How many bits will the qantization be done to have a 6Mb/s bitrate?

Hello everyone, My colleague and I are transmitting serial data over a visible light communication channel. How can we eliminate flicker? - i.e. when the signal is 01000100 the LED is dimmer than 01111011. When long strings of data are sent, it causes the LED to flash and it's detectable to...

letsa say i have an ak = cos ( k*Pi/4) + sin(3*k*Pi/4), the signal is discrete time, fundamental period N=12. the way i would derive its x[n] is.. Sum(k=0, to 11 of: 0.5*exp(j*k*Pi/4) *exp(j*k*w*n) + 0.5*exp(-j*k*Pi/4) *exp(j*k*w*n) + (1/2*j)*exp(j*k*3*Pi/4) *exp(j*k*w*n) -...

hello, i have a signal current I(t)=Acos(wt+theta) How can i calculate the signal power and noise power individually? thanks Reza

Hello everybody. I'm appologizing for a lame question, but taking for example A*cos(w*t) (whose spectrum is two impulses each of 0.5A in magnitude)-his power is 0.5A^2. It can be interpreted as a sum of squared magnitudes of its impulses. So, if I have a signal which consists of impulses...

I've been working on a guitar effects project for a while and I need a little help. What I want to do is add even harmonics to the signal. The way I've gone about it is this: I've used a diode to add harmonics to the signal. At very low volatages (<1v) the diode current may be approximated as...

x(t) = t, 0 \leq t \leq 1; x(t) = 2-t, 1 \leq t \leq 2; x(t) = 0 ,otherwise. I want to draw this signal, and I have something similar to this Is that correct? Also this is not periodic right? I just want to be sure 100% Thanks!

Hello! This is my first post here! :) I was just wondering, after experimenting with an indoor TV aerial, Wrapping Tin foil around the base, ensuring contact with the main metal conductor, I found that it improves the signal by around 5 times! (Positioned correctly of course). I was just...

Homework Statement If you had a function generator that generated wave forms so you could veiw them on a computer screen and it was showing a square wave with and input signal of 1V (amplituded 0.5 V) What would it look like if the signal was reduced by 10 dB. not sure what to do with...

The signal x(t) = e^{jt} is periodic. The signal x(t) = e^{-t}e^{jt} is not periodic. The decaying exponential makes the complex exponential decay and converge toward zero, but why is it not periodic? Also, this signal is not considered time limited since it never actually reaches zero...

Homework Statement What is the bandwidth of an AM signal if the modulating signal is x(t)=cos(2pi70t)+cos(2pi90t) and the carrier frequency is 10kHz? Homework Equations The Attempt at a Solution The carrier frequency is irrelevant because it just means the signal's spectrum is...

would it be possible in theory to take an audio signal, do an Fourier transform on it, divide all the frequencies by 10, convert it back to the time domain, transmit the resulting signal over 1/10th the bandwidth you would have originally needed, then reverse the process on the other end...