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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2answers
50 views

Signal rate, data rate and bandwidth in digital signals

I'm trying to understand the concept of signal rate and the relation between signal (baud) rate and bandwidth of digital signals from a book about data communication. First, the book distinguishes ...
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5answers
125 views

Why does differential signaling send complementary signals instead of just pairing the input and ground voltage?

I'm very new to EE, so please excuse me if this question is bad or has an obvious answer. After reading an overview of differential signalling, it left me wondering: Why does differential signalling ...
2
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0answers
57 views

Driving “Arcade CGA” monitor safely

I have some arcade machines which I build custom Linux PCs for. They all have 15khz monitors in them so I do some funky Linux stuff to output (what I think is) a correct signal to drive them. This is ...
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3answers
129 views

Driving 60 signals one at a time, in constant sequence

I have an application where I need to turn on/off one of 60 signals one after another in a constant order, ever repeating. (1, 2, 3, ... 59, 60, 1, 2, ...) Only one signal is on at any given time. The ...
-1
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1answer
36 views

How boost a DVB-C signal [closed]

I receive a DVB-C signal from my broadcast TV provider, and I use coaxial cables and some splitters to connect my three televisions to the coaxial wall-socket. Unfortunately I have problems to ...
-3
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2answers
48 views

What is the frequency at which meaningful data can be sent? [closed]

Excuse my poor use of accurate terminology, in advance. Is it possible to hear anything meaningful on a 1Hz signal? Are there any 1Hz signals? What frequencies can you hear natural phenomena? At ...
-2
votes
4answers
86 views

Baud rate calculation

I have an exam tomorrow and I'm confused on the following question, that may be asked in the exam: One byte data with parity bit by using asynchronous serial transmission with two stop bits. For ...
0
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1answer
57 views

SNR vs Signal Strength for digital throughput

I'm trying to compare two antennas, A and B for WiFi. A is showing: Signal Strength of -77dBm, but SNR of 9dB. B is showing: ...
1
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1answer
69 views

Differential signal processing and generation

I am trying to interface to a Mitsubishi central aircon unit. Based upon the manual, the internal units communicate over a differential bus (I hope is TDM). I have a screenshot of the signal: How ...
3
votes
4answers
249 views

How to prevent PA system from interference of 4G signal

I apologize if this is not the right place to post this. I am working on a small PA system for a weekly gathering. It catches the signal from wireless mics and output it to the speakers. I am pretty ...
2
votes
3answers
90 views

Wireless EEG electrode design

Currently, all 'wireless' EEG systems acquire signals from electrodes which are wired to an amplifier, a filter, a digitizer and then finally a wireless module. I want to design a system that's ...
0
votes
1answer
32 views

Measruement of RF Signal strength / phase difference

I would like to measure the signal relative strength and phase difference of two bluetooth(BT) receivers. and I found a chip that will do exactly that, AD8302 ...
0
votes
2answers
76 views

Eye diagram test

I am trying to perform a eye diagram test on a device to check its USB performanance. I am using a board "SQIDD" in order to perform this test. The following figure shows my test setup, I am using ...
2
votes
4answers
167 views

Thermocouple reading different from Commercial Datalogger when using Arduino

A K-type thermocouple is connected to a thermocouple breakout board that outputs 1.2V to 8.8V that covers the entire -260C - 1380 °C of K-type thermocouple. This output is than divided by ...
1
vote
1answer
34 views

What do you mean by cross range dimension of a radar's resolution cell?

I'm reading a book on radars and found this term. Any help is appreciated.
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2answers
106 views
0
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3answers
117 views

What is the deal with resonant frequency?

During the last day or so, I have studied the topic of resonant frequency over a few circuits. Now, I could easily see that every time my circuit operated upon that resonant frequency something ...
1
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5answers
152 views

How electrical signals converted into Digital (binary 1 0)

I already ask this question in yahoo and in Microsoft........they say that : did I mean to say how to convert analog signals to digital signals.....and they suggest me the theory of AD converter So, ...
0
votes
2answers
51 views

How does Signal-Noise-Ratio related to receiver power

If I have the instaneous Signal-Noise-Ratio (of the receiver), but no other information, and I am interested in the instaneous \$\mathbf{Power_{received}}\$, is there any relationship between these ...
0
votes
1answer
44 views

Wifi - How does channel difference between transmitter and receiver affect the signal/data?

When scanning a channel for wireless signals it is of course possible to pick up signals from surrounding channels. What I'm curious about (and forgive my n00b-ish-ness regarding the physics behind ...
0
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1answer
48 views

Frequency modulated voltage measurement with VFC voltage to frequency converter and counter

I would like to measure the voltage across a nonlinear high voltage pulsed power circuit. The pulse is an underdamped RLC discharge but with some non linearity in the inductance. A quarter cycle is ...
0
votes
2answers
124 views

Why is propagation delay of ethernet cables unaffected by cable length?

I did some searching on how propagation delay in ethernet cables is affected by the cable length. The answer seems to be that the delay is negligible until the cable length reaches a kind of threshold ...
0
votes
3answers
79 views

Signal to noise ratio for a non-physical property

The signal to noise ratio for a voltage, current, or power is easy to understand, but how do I calculate the SNR when the signal is not a physical property, but instead an abstract quantity? I'll try ...
2
votes
2answers
110 views

How Fuzz (audio effect) works?

I am relatively new to the world of guitar pedals, and I have recently (after a few failed attempts) built a successful Bazz Fuss. Although I've successfully built it, I'm not sure how exactly it ...
3
votes
4answers
118 views

Is quality of VGA Horizontal and Vertical sync Pulse relevant to be able to display on sensitive projectors

I am currently trying to diagnose a VGA problem on hardware A. Hardware A has some trouble sending display to certain projectors (while it is able to send display on most LCD monitors). Hardware B ...
1
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1answer
75 views

See if signal is amplified without an oscilloscope

I'm an electronics newbie, but I've had some experience with oscilloscopes in college lab. However, I need to design and wire a simple circuit that can read values from an electret mic. Since the ...
0
votes
1answer
56 views

Signal Generation with duration in VHDL?

Im writing a signal generator in VHDL and I would like to set the duration of the signal generated to 75ms, it is an out signal and my clock is 100 MHz, I would be glad if you can help!
0
votes
1answer
51 views

Why does frequency equal k/K where k=0,…, K-1 in Discrete Fourier Transform?

I totally can't understand why f = k/K. What does k, K means, respectively?. I really want to know what they actually indicate in real world. Or, please give me an example. I spent 2 days night but ...
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2answers
84 views

Multiplexing signals of two wires of a BNC cable and transmitting over a single wire

Background: I have a normal CCTV camera (650 TVL) . It requires a BNC cable in order to feed video signal from camera to DVR. Problem The problem is I have only a single copper wire from CCTV to DVR. ...
3
votes
3answers
112 views

How would I software-decode this 260KHz serial stream?

I've probed this serial stream coming out of a scoreboard controller and it seems like a proprietary protocol. How would I go about trying to software-decode this? The start bit is 7.8us long. All ...
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votes
1answer
57 views

Knowing the type of output signal

I have a digital photocell, where after dissembling, I see that it uses a ATMEGA88 chip(datasheet of the chip), but I do not have the schematic of the photocell. The whole photocell has only a pair ...
2
votes
1answer
59 views

Arduino: Generating time critical signals with interrupts

I have some problems to fully understand how interrupts on e.g. Arduinos/AVR are used in practice. Lets assume I want to generate a time-critical signal like PWM and at the same time be able to ...
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2answers
51 views

Audio - Current Graph

Mostly the signals out of a audio source is represented by Voltage/Time graph; like this - Then how would the Current/Time graph would look like, and what will happen if we alter it?
0
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1answer
38 views

Fourier transform of the components of bandpass signals

I'm referring to a book called Communication Systems by Simon Haykin, 3rd Ed. It says that a band-pass signal \$s(t)\$ with mid-band frequency \$f_c\$ and bandwidth \$2W\$ can be represented as ...
-1
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1answer
75 views

pulse amplitude modulation

Im bit struggling with PAM question. I've been trying to solve this for few hours but I am stuck at the stage where I need to sample m(t). Could you please help me with detailed answers and workings. ...
2
votes
2answers
129 views

GPS update rate

My thought process: I i'm am looking for a GPS that updates fast enough to actually read its position traveling 130 miles an hour ( I did some math and think 5 times a sec up date rate would get me 17 ...
2
votes
2answers
111 views

Down-Conversion of RF signal

I have a basic question about down-conversion of RF-signals. The ideal scenario is described as follows. Given a RF-signal (coming from an antenna), i.e., a real-valued function x(t), and given a ...
6
votes
2answers
474 views

How is signal 'discarded'?

It has always been a puzzle for me how a certain type of information can be discarded from a system when it is unused. Say, for example, the Internet Protocol (IP) specification states that packets ...
0
votes
1answer
85 views

Positioning a quadcopter using IR signal

I need to get an autonomous quadcopter above a bucket (60x40 Cm) and deliver a payload inside. The idea is to get near the bucket using the GPS. Then guide the copter by putting some IR emitters ...
3
votes
3answers
362 views

Solid State Relay Vs Triac

The general and simplified view of my circuit is something like that: Using a microcontroller I want to select between two sound signal sources (S1 or S2). S1 is a signal that comes from a ...
4
votes
4answers
138 views

Reconstructing Clock for Serial Signal

Suppose that I have a serial signal (example below), which is transmitted without an accompanying clock signal, I would like find a circuit (using discrete components / ICs, possibly an FPGA, but not ...
0
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2answers
49 views

How does the function inside the rectangular function work?

I'm looking at a Signals and Systems problem, and the question asks to show the inverse fourier transform of \$f(w)=\operatorname{rect}(\frac{w-10}{2\pi})\$ is: ...
0
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0answers
87 views

Which serial protocol or encoding scheme does this scoreboard use?

I am trying to decode a signal stream coming from a Nevco scoreboard controller: Packets like this are sent every ~2.7 ms. I suspect it is some sort of UART signal because it is on the RX line of ...
0
votes
1answer
53 views

looking to capture an infared code

I am trying to get an infared signal being sent from an emitter (think along the lines of a remote control). I know I can use a fotoransistor on a breadboard to capture/detect the signal, but I have ...
0
votes
1answer
57 views

How much is the noise of a multiplexer for analog inputs?

I have 4 sensors, each have with two differential output (S- and S+) that I need to use in a differential amplifier (with a gain equals to 1000 in my case). The difference between S- and S+ is ...
0
votes
0answers
42 views

Use Earth and Ground Rods as Tip and Ring for a Modem

My co-worker and I recently tested this theory out with two Cermetek 1794A modems. Datasheet: http://www.cermetek.com/Catalog/High-Speed-Modems/DataSheet/CH1794A_607-0020.pdf Now first, we did two ...
2
votes
1answer
69 views

Mirroring (flipping) a voltage signal?

Which circuit can convert the input voltage signal to either output signal A or B as shown in the image below? Background info: {Update1:This is the signal from a Passive Infrared (PIR) Sensor ...
0
votes
1answer
51 views

output of a cascade system with known impulse responses

We have a system \$x(t) -> |h1(t)| -> |h2(t)| -> y(t)\$ and \$x(t)= e^{(-2t)}u(t)\$ and \$h_1(t) = h_2(t) = e^{(-2t)}u(t)\$ and we want to find the output \$y(t)\$ of the system. What I am ...
1
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2answers
115 views

system and properties of linearity,causality, time invariance, stability, invertibility

I have a system and I want to find which properties hold for this system $$ y(t) = \left.\begin{cases} x(t) & t \geq 1 \\ \\ 0 & -1 < t < 1 \\ \\ -x(t) & t \leq -1 \end{cases} ...
4
votes
2answers
194 views

Why does more bandwidth mean higher bit rate in digital transmission?

I understand that similar questions like this one have been asked before on this site, listed below. However, I am confused about the answers. If I explain what I think I understand, can somebody ...