Signal Definition and 935 Threads

This might be either an obvious one, or I might be totally off track. I haven't seen, or been able to find neural action potentials being referenced as signal transductions. Aren't they signal transductions? And if not (say if action potential is only referenced to the change in potential)...

Homework Statement Consider the circuit in the figure and calculate V1, V2 and IA. Notice that the symbols V and A represent, respectively, an ideal voltmeter and an ideal ammeter. Homework Equations Ohm's Law $$V=RI$$ KVL The sum of the voltages of a mesh in a circuit equals zero. We...

ie: http://m.eet.com/media/1072296/RFFig84.jpg I am 99% sure the answer is: no, it can't. I've read that DSB-SC demodulation requires the carrier frequency to be put back into the signal at the receiving end prior to demodulation (or as part of the demod process), and that if its too out of...

How signal is transmitted through only one wire (red) of simple RCA cable? What is use and how works ground wire (black)?

Roger Penrose, July 2017. Correlated "noise" in LIGO gravitational wave signals: an implication of Conformal Cyclic Cosmology

Hi Guys, I have a question on the need for Digital to analog converters in Transmitters. To elaborate bit further: 1) Because of the advantages of the Digital signals, most go the signal processing in wireless communications is performed in baseband. But my question is: Since digital...

Hello everyone, I'm actually working on developping a phase shift sensor using one phase modulated signal, i know that the title is confusing beaucause the phase shift measurement need two signals , I'm trying to do this with the zero crossing method so if I could found the timestamps of the...

Hi, I'm a new member in this forum. my question : How calculated the normalized error with two signals?

I have one question: Many times, in order to test whether an outcome should be considered as "Signal" (S) or "Background" (B), we are using BDTs which we have trained on known outcomes... I was wondering though, the outcome of being S/B is binary : either it's signal or it's not... the only way...

Hello , This doubt arose while studying chapter on semiconductor devices in grade 12 of high school physics . Please clear a doubt in as simple language as possible . In order to be specific with my question I need a diagram which is exactly as mentioned in the video below . Kindly see Note...

Homework Statement Q1. A hydraulic jack has a load piston diameter of 150 mm, and a plunger diameter of 25 mm a) Ignoring loses, calculate the force needed on the plunger to raise a load of 2500 kg b) Calculate how many stroke of the plunger will be required to raise the load 180 mm, if each...

Hi Guys, Can Some one Help me to Figure Out how can i Convert Voice Signal from 3.5mm Jack to Voltage. Though the voice signal has low signal strength can i boost it using amplifer and to get output in Voltage what is the Process i am not figuring out the perfect way. Sugest me your Option...

Hi, so i am doing measurements with a pulsed laser using an oscilliscope. The signal has been ok (stable) until this afternoon when I noticed the signal started pulsating. The baseline of the signal suddenly jumps up and the baseline becomes larger, and then go down to normal.. and it keeps...

Homework Statement Hi guys, I have the following transmitted power signal: $$x(t)=\alpha_m \ cos[2\pi(f_c+f_m)t+\phi_m],$$ where: ##\alpha_m=constant, \ \ f_c,f_m: frequencies, \ \ \theta_m: initial \ phase.## The multipath channel is: $$h(t)=\sum_{l=1}^L \sqrt{g_l} \ \delta(t-\tau_l).$$...

Homework Statement Homework Equations Manson method The Attempt at a Solution I used Manson method. I am not sure this is the best result. can someone use MATLAB or some software to solve this quickly ??

I seem to have a lot of trouble understanding radio carrier signals I have read a bunch of stuff online and seen videos trying to explain it but I just can't understand it! Could some of you who understand try and give me some analogies or anything that might help me out? Thanks alot!

Homework Statement "The complex power spectral density is : S(jw)=(1/(w*(w^2+a^2))*e^j90 Find the form and duration of the signal." Homework Equations Any ideas on how to solve this ?[/B]The Attempt at a Solution What I've managed to calculate so far is: http://tinypic.com/r/zydamr/9

Homework Statement Determine whether u[n] - u[n-4] is a power or energy signal. Homework Equations The Attempt at a Solution I am stuck here. I don't know how to simply further. Please help.

Hi, my question may be too open ended in which case some help defining it would be helpful. The signal I wish to measure is estimated to be ~50 pico volts in amplitude generated in an HF AT-cut quartz crystal. Basically all the signal power will be at the fundamental mode resonant frequency...

I am contemplating about pursuing EE bachelor. My goal is to deal with antennas, signal processing, electronic communication, etc. But all the curricula that I have examined (USA), universities don't seem to offer any courses on antennas. Sig proc - yes, and so are circuit analysis present there...

I have a typical problem. I have two bars mobile signal in my attic - none at ground floor level. The reason is a roadside pole transmitter less than 500m away installed down in a dip behind houses (duh!) An electrically powered signal booster is illegal in the UK which atracts a £5000 fine...

Hi, I am measuring an analog voltage with an Arduino analog in. The analog voltage comes from a cable which also contains digital signal wires. Do I need to separate the analog and digital signals using separate cables? If so, does the analog voltage signal cable need shielding? And if so, how...

Homework Statement I have an impulse response h(n)=e^(0.1n)*[u(n)-u(n-8)] and an input x(n)={0,1,2,3,0}, how do I find the output y(k)? [/B]Homework EquationsThe Attempt at a Solution i don't even know how to solve. should i try convolution or should i substitute the values of x(n) in h(n)...

Homework Statement Homework Equations Δφ = 2π (Δr/λ) The Attempt at a Solution I understand how to get the phase difference, but is the equation for the combined wave (second last line) just something I should memorize? Also, where does the sin term go in the last line? And why are the...

Hi, I need to buy a bridge amplifier for my load cell. I need to be able to take at least 350SPS (samples per second). The only load cell amplifier I can find within my budget states that it has a selectable 10 SPS and 80 SPS output data rate. Heres the link to the amplifier...

Hello Physics Forum people! I am working on a project involving indoor mapping, and I have just received 10 SRF02 ultrasonic range finders to hook up in an array to measure distances using sound waves and use this data to map out buildings. However, we are looking to receive the "raw signal...

Homework Statement Consider the frequency-modulated (FM) signa A(t)=A0sin[2πfct+Δfsin(2πfmt)/fm] , where fc = 3.5 kHz, fm = 88.1 MHz. What is the bandwidth of the signal? [Note: You may take sin≅ and cos≅1 for x (in radian) << 1.] Homework Equations A(t)=A0sin[2πfct+Δfsin(2πfmt)/fm] The...

I'm not realising this thing.

Hello, I'm using a lock in amplifier (model 5210 from signal recovery) for some experiments with photodiodes. Firstly, there is an optical chopper that "feeds" the lock in (reference signal). My input is a photodiode (in current mode). The problem is,the unlock (unlk) light is always on in the...

Homework Statement Derive the expression for coefficients of Fourier series in exponential form for the sequence of rectangular pulses (with amplitude A, period T and duration θ) shown in this image: Derive the expression for signal power depending on the coefficients of Fourier series...

What is the prevailing opinion among astronomers about the most plausible explanation for the Wow! signal? I was just reading that Jerry Ehman, the man who discovered the anomaly in 1977, believes the most likely explanation is a signal from an extraterrestrial civilization...

I have a question regarding how a Yagi type antenna radiating its energy with respect to faithfully replicating the original signal. So let's say you have a FM modulating signal, F(x(t)) whereas x(t) is the data, and F(t) is the carrier, so basically x(t) would FM modulate the carrier F(x)...

Hi, I am a little "confused" of how to treat a problem stating: suppose you expect 1.25 background (SM) events from one measurement. During one particular measurement, you observe 5 events. What's the probability that you discovered new physics? The standard/basic way to go about it is to...

hi, im trying to distribute a clock signal using a clock fanout buffer. I have an oscillator and i need to get its clock signal to 4 other devices. My first idea was to supply the clock signal of the oscillator to a clock buffer. I have chosen this clock buffer...

Homework Statement f(N) is {3, 4, 5, 6, 7} It starts at 5 meaning f(o) is 5. i have to find f{2N-1} 2. Homework Equations [/B] f(N) is given, so first find f(2N) and then delay by 1. The Attempt at a Solution f(N) is {3, 4, 5, 6, 7} finding f(2N) f(0) is 5. f(2 * 0) is 5 f(-1) is 4. f(2 *...

I am studying The Art of Electronics and am confused about this particular part about a signal rectifier. In the first picture above, the first cap and resistor function differentiate the signal, and the signal passes the diode if the voltage is > .6V. The second circuit improves this by...

Looked at a RF spectrum that came from the IF output on a radio so it was not tuned thru the radio filters, just whatever the HF antenna was capable of. A pulse went across the entire spectrum slow enough to see it sweep across the screen. The pulses were not regularly spaced but came in...

Hello all, I'm an undergraduate at a large research university in Massachusetts working in a lab where my group contributes to the Muon g-2 experiment at Fermilab in chicago. Essentially what I'm working on is optimizing an optical rotation (Faraday) magnetometer system for use in magnetic...

I have a simple complex exponential signal of the form x(t)=ejωt. To find period of the signal I tested if x(t)=x(t+nT) for all n: ejωt=ejω(t+nT) ⇒ ejωnT=1=ej2πk where n and k are integers. Then I find a general period expression as T=2πk/ωn Period T means it is the least time a signal...

Hi guys, If i put mobile phone into micro oven, Is this prevent mobile signal

I am doing an experiment in which an audio voltage signal can be obtained and saved as .csv (or other formats) by oscilloscope. In a second step I want to recover it into audio voltage signal and input it into a loudspeaker. Then how can I do in the second step? Or how to transverse a .csv (or...

When antenna receive the radio signal does it reduce the actual radio signal strength or strength indeed depends on the dispersion loss and other dielectric absorption? If antenna doesn’t reduce the radio signal strength(power), how it generates the current in the receiving antenna circuit? How...

I am a high school student interested in electronics. I have been able to understand almost everything about electricity and digital computers mosfets, logic gates,memory,cpu, fetching ,decoding, executing ,clock cycles, etc. except there is one thing that I can't seem to grasp my head around...

Homework Statement Assume a wave packet is has contributions from various frequencies, give by g(ω)=C for |ω|<ω0, and g(ω) =0 for elsewhere. a)What is the signal strength as a function of time, i.e., V(t)=? b) Sketch g(ω) and V(t); You can use fooplots.com, for example, or python. c)...

Hi Guys, I'm having trouble with the following: A finite-time signal is the result of a filter G(t) applied to a signal. The filter is simply “on” (1) for t ∈ [0,T] and off (“0”) otherwise. If x(t) is the signal, and x(ω),its Fourier transform, compute the Fourier transform of the filtered signal...

hi, i need a 28.8MHz clock signal (digital/square wave). Unfortunately this specific frequency is hard to get so i need to make one myself. I guess the keyword here is "frequency synthesizer"? Or how would you approach this? (to get the 28.8MHz clock signal out of other more commonly available...

Homework Statement Find power of signal A u(t) A is constant like 5, 6 some value.[/B]Homework Equations Power is integration over -T/2 to +T/2 of [x(t)]2 dt The whole divide by T The Attempt at a Solution Power is integration over -T/2 to +T/2 of [A u(t)]2dt[/B] The whole divide by T So...

hi, i was wondering how its possible to split a clock signal provided by an oscillator in order to use it to drive multiple devices with this one split clock signal. Let's assume we have a kind of USB device (like an USB stick), that gets its clock signal from an oscillator. Let's say i would...

I am new to this forum. I am an electrical engineer designing frequency synthesizers for electronic test and measurement equipment. I have a design problem and I think that number theory could help me solve it. I'm not a mathematician, so I will state the problem the best I can. Definitions...

Homework Statement The analog signal x(t) = cos(2pi f t) is sampled at a rate of 1 kHz, using ideal impulse sampling, to obtain the sampled signal x^(s)(t). The sampled signal is then sent through an ideal lowpass filter with transfer function H(2pi f ) = 0.001 rect (0.001 f ). (a) If f...