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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14 views

Link integrity test pulse vs carrier signal

Ethernet uses a refinement of ALOHA, known as Carrier Sense Multiple Access (CSMA), which improves performance when there is a higher medium utilisation. When a NIC has data to transmit, the NIC ...
2
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1answer
53 views

Remove DC offset and rectify

I'm using ACS712 hall effect current sensor to detect presence of current in the power line of a remote device. I don't need exact current value but rather just want to know if it's above certain ...
-5
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0answers
37 views

How 'lost carrier' and 'no carrier' detected? [on hold]

By using command 'show interface ', one of the line of the command's result is like below. 0 lost carrier, 0 no carrier How they are detected?
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1answer
29 views

Distance confusion about Shuncom SZ05-ADV ZigBee module

I ordered this module looking at the datasheet that it has a range of 2000m LOS distance. But now when I test it, I can receive signal from a maximum of 50m distance! It sends 2.4GHz signals. As far I ...
2
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3answers
48 views

Measuring direction of object (or angle of signal origin)

I am interested in somehow tracking the "compass" direction of a moving object from a reference-station -- in other words, something similar to submarine sonar systems (although I'm unsure how those ...
-1
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0answers
42 views

Is it possible to transmit Coaxial signal before a cable TV box (wirelessly or otherwise)? [closed]

I just moved into an apartment that has no cable jack in the living room. From what I see, I could do one of these things to get the Comcast signal to my TV: Request that a new RG6 Coaxial cable be ...
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2answers
79 views

What is “M” in Hartley's law?

If Hartley's law is: $$ C = 2 B \log_2 M $$ I know this equation is part of calculating the capacity of a channel. I also understand that: \$C\$ is the digital bandwidth, in bits/second \$B\$ is ...
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2answers
71 views

fourier transform for non-stationary signal

I have read that for non-stationary signal we break the signal into smaller segments by applying a window function . My question is how this can help to make the signal has a fixed features or to ...
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1answer
52 views

Space Vector Modulation

Im looking to learn more about this topic so that I can implement it in an amplifier design. I've read around and understand most of the math behind it, but I'm still a little fuzzy on how to ...
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1answer
58 views

Response of a stable second-order transfer function to a unit sine wave input

In the lecture slides from my university it says that: "The response of a stable second-order transfer function to a unit sine wave input is:" ...
0
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0answers
32 views

Bypass switch for amp

I've just successfully completed a CMOY amp and I'm pleased with the result. However, I want to be able to hear the difference between the original signal and the amplified signal, so I put a switch ...
4
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1answer
49 views

Analog off board connectivity

I have a board that I intend to control with high fidelity differential analog, I'm aiming at one part in 216. I want to connect the two boards with a COTS connector that solves most of the pick-up ...
2
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2answers
83 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 ...
2
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5answers
172 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
66 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
134 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 ...
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1answer
46 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 ...
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2answers
49 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
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4answers
102 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 ...
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2answers
78 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: ...
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1answer
77 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
268 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
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3answers
96 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 ...
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1answer
46 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 ...
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2answers
83 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
192 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 ...
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1answer
40 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
120 views
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3answers
131 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 ...
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5answers
190 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
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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
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1answer
50 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
56 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
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2answers
139 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
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3answers
82 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
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2answers
116 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
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4answers
137 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 ...
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1answer
80 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
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1answer
63 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!
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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
97 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
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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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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
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1answer
66 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
52 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?
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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
85 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
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2answers
150 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
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2answers
119 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
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2answers
475 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 ...