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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Signal representation in frequency domain

My teacher taught me that the frequency representation of time limited signal will be band unlimited. Also the frequency representation of time unlimited will be band limited. i.e frequency domain ...
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1answer
74 views

What is maximum range of voltage measurement?

Another 'Basic EE' question here (from a mathematician). Being rather ignorant of the matter - I would hazard to guess that there is some physical limit to the range of voltages that can be ...
0
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1answer
35 views

How to measure the signalling speed of Gigabit optical ethernet?

Signalling speed of Gigabit Optical ethernet is 1.25 GigaBaud . I tried some methods such as measuring the UI of the eye diagram on a sampling oscilloscope by sending some random test patterns , high-...
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0answers
38 views

Telephone connected signal [on hold]

When we dial a number after the reciever pick up a counter starts it means a signal from the center has been sent to our telephone or cell phone. I want to now what is that signal (frequency , time ...
0
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3answers
74 views

PNP transistor instead of mosfet to register small clock and data signals [on hold]

I have a device that outputs -0.2v clock and data pulse (It works on CR2032 (3v) and I assume it's CMOS), I want to register that signals on arduino in simpliest way. Since no mosfets have threshold ...
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1answer
97 views

How a signal is transfered with only one connection in a simple circuit [closed]

I need some explanation to something i experience. I use an Arduino (DUE) to create some audio waveforms, and a laptop as an oscilloscope to watch the waveforms (and for programming - powering the ...
0
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0answers
21 views

Channel Capacity Clarity needed

1) Suppose a Noiseless Binary Channel, who's input is reproduced exactly at the output. Let X be the transmitter and Y the receiver (i.e (X=0----->Y=0 and X=1-----> Y= 1)) I understand intuitively ...
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1answer
42 views

Up/Downconverter issues

I am having some issues with my up and downconverter. What I'm trying to do is to receive a 125 kHz signal, upconvert it to 433.125 MHz, transmit it, receive that signal, and downconvert it back to ...
2
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3answers
210 views

Improve Rise Time on 1Hz Signal

I am using a MCP79410 real time clock to generate a 1Hz square wave signal (50% duty cycle) for a low power display (Sharp Memory LCD). Without this signal charge builds up and the pixels show burn-in....
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1answer
46 views

What does an “ac coupled signal” mean?

I've heard this term many times from many different sources, but none of them gave me a definition. Here is my understanding: "coupled" means "connected together". If two circuits are "capacitively ...
0
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0answers
37 views

3.5 mm male to RS232 male : wiring problem

I am trying to use an old datalogger thermometer (Tenmars, TM-747DU-4 Channel Datalogging Thermometer, Webpage link) which has a 3.5mm female connector (audio connector). The wire supplied with this ...
0
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1answer
46 views

Design of 3g signal repeater [closed]

I am interested in 3g signal repeater and decided to design one. I am planning to just buy 2 antennas and design the amplifier circuit only. my questions are: Should I care much about the antennas? ...
0
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0answers
36 views

Coaxial Cables: RG6 or RG6 Low Loss?

I have a 50 foot zBoost RG6 low loss coaxial cable and it's not long enough for what I need. I need a 100 feet of cable (that will work outdoors) and I'm stuck between a rock and a hard place in ...
0
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1answer
46 views

Temperature sensor output signal to TTL

I'am looking for a circuit schema to convert 0.5V square signal from 2-6 kHz into square signal of 5V on output side. What I need is to count / measure frequency with microcontroller. I have a SEABIRS ...
0
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1answer
53 views

Signal conditioner for a piezoresistive pressure sensor

I have an instrumentation amplifier which output voltage equation is given.The piezoresistive pressure sensor in Figure E3.12 consists of a bridge of four silicon strain gages of 4000 ohm and 1 mV ...
0
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3answers
59 views

Can you measure voltage along a wire a multiple points simultaneously?

Basic EE question here. Suppose I have a piece of wire a foot long. Suppose there is some signal (for example a clock signal) going through the wire. Is it possible to simultaneously measure the ...
0
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0answers
25 views

analog filters- dispersion, ripple and windowing

What is the adventage of using a rectangular window instead of hamming? Is it necessary to minimize the ripple in the pass band or in the stop band? If I put a periodic signal through an analog filter,...
0
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0answers
62 views

Finding UART pins on a PCB header

I have a PCB with some headers exposed. I know for certain that some of those pins are UART connections (RX,TX, Ground). I'm hoping to find RS232 with TTL voltage levels but this is just an assumption....
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1answer
34 views

What is the type of the wifi interference to ZigBee? Multiplicative or additive?

As we all know, the cross technology interference is a critical problem. CTI means that different communication technologies operate on the same spectrum (e.g., 2.4GHz), and this would lead to the ...
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2answers
75 views

Type J Thermocouple Signal Conditioning to 0-5V

I've been working with signal conditioning, thermocouple out specifically. I'm working with a span of 450 °C, that is, from -50 °C to 400 °C. For those values of temperatures I get, according to the ...
0
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1answer
29 views

Generate +2V Offset on a +12VCD Supply line

I have a 12VDC @50mA_Max supply line. I need to inject a +2V 50us offset pulse to the +12VDC line, having an effective +14V for 50us. I have access to an external power supply, where I can have ...
0
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1answer
62 views

“Tagging” Data traveling over serial port?

If I'm reading data from multiple channels (UART) of a microprocessor, but I want it to be continuously read, I imagine the logical thing to do would be to cycle through the channels and output data, ...
0
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1answer
56 views

one-way RF signal diode

Is there a special diode or band pass filter that will only allow RF signal to go though a wire in one direction like a diode does with electricity?
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0answers
60 views

RS 422 signal voltage booster

I have RS422 output signal with 2.6V peak to peak, However after distance 25 meter this signal voltage is attenuated upto 0.8V and receiver is not able to detect signal. Is there any IC for boost this ...
1
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1answer
81 views

How do I stop coiled (telephone) wire blocking signal?

This circuit is working just fine if the output signal uses a straight wire, even if it is a very long wire with say a 1K resitor added to the end of it. However, the signal does not get through when ...
3
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1answer
65 views

How can I create two ac signals with a voltage controlled phase offset?

Is there a fairly straightforward analog circuit (resistors, capacitors, transistors, etc) to generate two sine waves of the same frequency and introduce a relative phase offset between them? So I'm ...
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2answers
63 views

What is a typical value for the gain of a smartphone's Bluetooth (or Wi-Fi) antenna? [closed]

I can't find specific values for transmitter and receiver gain anywhere. Very often the Bluetooth module is together with the Wi-Fi module, so a Wi-Fi antenna gain value will help me as well. I need ...
0
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2answers
98 views

How to read out data from this moisture sensor?

I found a cheap moisture sensor on Ebay that only came with the schematic attached. The moisture can be read with an analog or digital signal. However, I am wondering how the opamp creates a digital ...
0
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1answer
79 views

Falling edge detector using BJT

I'm trying to build what is basically an electronic push button switch - something that would switch an led on an off with the same signal . I figured doing this would require a falling edge detector ,...
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1answer
31 views

Fetch RSS value using Nordic NRF24L01 module and RadioHead library

RadioHead provides a lastRssi() function (http://www.airspayce.com/mikem/arduino/RadioHead/classRHGenericDriver.html#ab04f2ca335d89f5fac1d213c0aea9da2) to fetch the ...
3
votes
2answers
139 views

What is the source of this shape on my USB eye diagram?

I have designed a USB device around an STM32F105. It is USB 2.0 Full Speed CDC device configured as a Virtual COM Port using ST's USB Library. It uses the STM32's built-in PHY, and runs at 12 Mbps. ...
0
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2answers
110 views

What is the difference between the terms wave, waveform, and signal?

What is the difference between wave, waveform, and signal? Or do they have the same meaning? Can they be used in place of one another?
2
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2answers
85 views

Lengthening button press signal

I'm trying to rewire an arcade game, and I need one button (a simple microswitch hooked up to the coin acceptor) to have a longer press than a coin passing by provides. I'm not sure exactly how long ...
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0answers
27 views

Resonant RC Series and deriving equivalent circuit

How is it that this is equivalent? Assuming all transients have died out. vi = Vcos(omega*t) The fake input was defined as: \begin{equation} v_{cp}^\sim = \frac{V_i}{1+j\omega_1RC} e^{j\omega\\_1t}...
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1answer
95 views

Small signal equivalent circuit BJT question

This circuit is two BJT transistors in so called 'darlington configuration'. I want to analyse this circuit for AC signals (where the capacitors are shorts). The question is to calculate Delta_V_L/...
0
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0answers
34 views

Simulink how to convert Duty Cycle to reference voltage signals(Uref)

In Simulink I am creating a DC-DC buck converter using Average-model based VSC Universal. But one input of VSC is in Uref. For this case I need to convert Duty Cycle (D) into Uref for Input. Because ...
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2answers
48 views

Wireless 2.4GHz to Bluetooth? [closed]

I've been wondering about this for a while; I have a Wireless 2.4GHz keyboard that requires a USB reciever to catch the signal. How great would it be though if I could use it on my phone, for ...
0
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2answers
70 views

12-bit output to +/- 10v

Suppose we have a signed 12-bit output which is capable of representing both positive and negative numbers, how can this be converted to a +/- 10v signal using DACs, op-amps, etc. For example, 1100 ...
0
votes
2answers
70 views

How do I determine the start and end of the wave?

I am facing a bit of a challenge in trying to understand basic concepts or terms within the signal world. I have a number of values retrieved from a sampled signal that is generated randomly for no ...
0
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1answer
79 views

Using an earthed function generator with an earthed oscilloscope and ground loops

I have a function generator and I noticed that its DC GND is internally wired to its earth pin. Similarly I have an oscilloscope and I noticed that its DC GND is also internally wired to its earth ...
0
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1answer
33 views

Lock-in amplifier output to spectrum analyzer

In several lock-in amp tutorials and experiments (including at the end of “Physics 111: Low Light Signal Measurements” on Youtube), the lock-in amp X or Y output is applied directly to a spectrum ...
0
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1answer
66 views

Analog signal vs. Alternating current

I am seeing that both of the analog signal and alternating current is represented by the same graph: As far as I think I know, an alternating current travels back and forth with gradual changes in ...
0
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1answer
27 views

Actual procedure used to establish a MW link budget in telecom?

If it possible can someone share with me the actual procedure used (Not the theoretical steps in book !) like in Huawei or others telecom vendor to establish a Microwave Link between to sites Like ...
3
votes
1answer
62 views

In a Delta-Sigma ADC, does noise shaping bring the noise to the signal's frequency?

I'm trying to understand the Delta-Sigma ADC. It is known that it pushes the quantization noise to be in the higher frequencies (noise shaping). Since I don't quite understand how this works, I ...
0
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1answer
57 views

3.3V to 5V logic converter using p-channel mosfet

I am trying to convert a 3.3V logic signal to 5V logic signal. I am using a p-channel MOSFET and I can not get it to send the full 5V signal through. Below is the circuit I am using.
0
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0answers
37 views

Low pass filter for differential signals

I'm building an adc and amplifier circuit for sensing a differential signal out of a pressure sensor. My plan is to use a circuit very similar to what is seen below: The total differential output ...
0
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0answers
30 views

Determining Sampling Rate of Analog Signal from Modulated Signal

I'm studying for a final and have a question. The image above contains a graph of time and signal duration. I'm used to seeing the PWM/PPM/PCM/etc rather than this type of graph. Am I correct in ...
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1answer
74 views

Problem with implementation XAPP495 [closed]

I'm working on XAPP495 to show a signal which is throughput of a HDMI signal from my Laptop I do this steps: created a new ISE project added all of the .v files from XAPP495 added dvi_demo.ucf set ...
2
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0answers
83 views

Q: What is the power of this signal

Determinate the power of the discrete signal: $$x[n] = u[n] + (-1)^n + (\frac{-1}3) ^n * u[n]$$ where: $$u[n] = \begin{cases} \ 1, & n \ge 0 \\[2ex] 0, & n \lt 0 \end{cases}$$ The answer ...
0
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1answer
35 views

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 ...