A transmission line may refer to a cable or assembly that is designed to carry radio frequencies and must consider the wave nature of the signal. Coaxial cable is an example of a transmission line. It may also refer to high-voltage power transmission lines, used to transfer power from generating ...

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Behaviour of reflections along transmission lines

I have another question about transmission line behaviour. People always tell (at least I read it multiple times in various articles while googling) that when one is measuring the voltage along a TL ...
4
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1answer
45 views

ECL output termination

This is a rookie question, but I'm quite confused about the ECL termination used on the ADCMP565 evaluation board First, in the IC datasheet, they show how to terminate the ECL outputs to drive 50Ω ...
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1answer
32 views

Low weight split core transformer on 11kVA transmission line

I've seen transmission line energy harvester's that utilise a split core transformer. Here is an example. However, I fail to see how this is possible when a transformer cores which are small enough ...
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1answer
27 views

Calculating power received and V (rms) given powr loss

The transmission line cable below is 10m long and has a power loss of 1 dB/m at the frequency of the source. What is the power received at the receiver (in dBm), and the voltage (RMS) of the signal at ...
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1answer
32 views

generator impedance and resistance

If i have a generator with a reactive component and resistive component are these in series of parallel? and When considering the impedance of a transmission line, should the impedance from the ...
2
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1answer
71 views

Understanding Ohm's law(?) for transmission lines

I have this easy schematic Next to this is stated that: $$Vb = \frac{Z_{in1}e_{b}}{R_{B}+Z_{in1}}$$ non Latex-version of the formula: Vb = (eb*Zin1)/(Rb+Zin1) I would like to know from where ...
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3answers
92 views

CAN bus layout design

I am trying to design a CAN bus node. The CAN bus shall be split-terminated with 120Ohm, 60Ohm for each line. Therefore i tried using this paper to calculate a characteristic impedance of 60Ohm for a ...
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0answers
25 views

difference between rising and falling time from the pulse response of transmission line

Attached is output pulse response of a transmission line (s-parameter). In the high-speed serial link design, we usually see more # of post-cursur ISI than pre-cursor ISI. One of the main reason is ...
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3answers
80 views

Input/output impedance of microcontroller

how to calculate the input and out put impedance for a micro controller , for the purpose of modeling in LT spice , for example RX610 family from Renesas For example the lumped characteristics can ...
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1answer
39 views

coupling in transmission line

I have a very basic and rather silly question which I have not found any suitable answer yet. Suppose I have 2 transmission lines. One carrying a high frequency sinusoidal signal. Is there coupling ...
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2answers
564 views

High voltage three phase transmission lines

The high voltage transmission lines in North America looks like this. If a three phase balanced circuit uses three voltage sources, would that mean that this pole in figure one is carrying the ...
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2answers
116 views

How is a 50Ω “back-termination” accomplished on a scope probe line?

I've just been watching Jim Williams' very excellent video on Measuring Switching Regulator Noise. At 1:58 Jim mentions a "50Ω back termination" in the probe setup that looks something like this (but ...
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0answers
37 views

reflected wave in transmission lines

I am trying to understand reflection in transmission lines. My text book says - Incident Voltage +Reflected Voltage = Transmitted Voltage. Incident Current - Reflected Current = Transmitted Current. ...
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37 views

What does K(k) mean in a transmission line equation

I'm reading through a book I have about transmission line structures. They frequently use the math: $$\frac {K(k)} {K(k')}$$ For instance, characteristic impedance: $$Z_0 = Constant \cdot \frac 1 ...
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1answer
95 views

Distributed Transmission Line, Characteristic Impedance in AWR Microwave Office

I am trying to design a distributed amplifier in which the parasitic capacitances of a small-signal FET model are linked to inductors to form a distributed line across the drains and gates and I'm ...
0
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2answers
34 views

Redundancy for a databus transmission

I'm going to start a project in my University in a few week. Since it is a collaboration between my University and a very important company I cannot say too much about the project itself. So I try to ...
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2answers
261 views

Transmission Line: characteristic impedance matching

The textbook explains a situation in which when you have 2 unmatched transmission lines (different characteristic impedance), you can connect a new line in between such that the input impedance would ...
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3answers
51 views

How does async data transmission actually work?

I think I understand synchronised data transmission between A and B. They share a synchronised clock signal that indicates when the transmitter is sending a bit and the receiver should read the value. ...
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1answer
40 views

How is data transmitted on different media? [closed]

Thinking about computers primarily, I'm trying to get my head around how data is transmitted along various transmission media. In particular, I'm getting confused between the use of electromagnetic ...
3
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1answer
96 views

Running A Webcam 600ft underwater

I doing a bit of research into the concept of using webcams to watch crab and fish traps to solve the problem of hauling up empty traps. Depth 100 fathoms = 600 feet. Obviously wireless won't work. ...
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1answer
71 views

Simulation of TDR using LTSpice

I'm trying to simulate a TDR based on the figure below, and one of the scenarios is a short circuit. The simulation should last for 140ns. The parameters are \$Z_A = 50 \Omega \$ \$T_A = ...
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1answer
53 views

why step up transformer is used at the generating station to step up the transmission line voltage?

how it helps by stepping up the generating voltage at the generating station to minimize the losses of a transmission line? when voltage increases current also increases. so it should increase the ...
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1answer
61 views

Termination resistors usage

My doubt pertains to the usage of termination resistors. This is a continuation of the discussion I saw in this link - Termination resistor. I understand that any transmission line can be simulated ...
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2answers
58 views

Distance on transmission lines traces

I am designing a PCB with a couple of transmission lines. I have already calculated the thickness and width of my traces based on the substrate height and dieletric to have a 50 ohm transmission line, ...
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1answer
60 views

Output Voltage of Quarter Wave transmission line

Consider a 300 ohm lossless line operating at 1GHz which is connected to a source of 10v and impedance of 50 ohm. What is the magnitude of voltage at the open circuit end?. My attempt: At the ...
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1answer
54 views

Transmission lines/Antennas power delivered to a load, why halved?

When seeing transmission lines and antennas in class we saw that the power delivered to a load is equal to: $$ P = \frac{1}{2}\cdot \left | I \right |^{2}\cdot Re\left \{ Z \right \} $$ Where I is ...
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76 views

input impedance of lossless transmission line

can anyone explain this for me? firstly I added up the impedance of transmission lines and found Zin, but it seems to be very wrong. and I don't understand how they came up with these formulas ( ...
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2answers
150 views

BNC cable's characteristic impedance and voltage drop

As far as I understand, the characteristic impedance matters when a signal is oscillating since the BNC coaxial cable can be modeled as having inductors and capacitors as in the figure: I have ...
2
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1answer
99 views

A question about the sound of corona discharge

In my collage, We were doing an experiment of the air's Breakdown voltage . At the end of the experiment we were listening to the sound of corona (electric partial discharge). The power supply has the ...
6
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2answers
596 views

Why skin effect happens at the center of a conductor?

I was reading an article about Skin Effect. I know what skin effect is, but I wanted to know what causes it. Why is the back EMF strongest at the center? Why is it not distributed uniformly at the ...
2
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1answer
101 views

No driver IC on net in Hyperlynx problem

I am getting the 'no driver IC on net' problem in Hyperlynx signal integrity software. Does anyone have any idea bout it? This is my PCB: It has an SMD connector and an AD9767 DAC. I have added the ...
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2answers
144 views

Why is AC impedance 1.3 times the DC resistance? [closed]

I have seen several times that AC impedance is considered to be 1.3 or 1.5 times the DC resistance. But, never found the reason behind this consideration. Is it an experimental or observational ...
3
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1answer
66 views

Transmission lines and superposition

Below is the circuit in question. Good evening, I'm working on a problem that requires me to graph voltage at point A between -10 ns and 120 ns. I know that we must factor in wave reflections that ...
2
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1answer
49 views

Chamfer Geometry for GCPW and Microstrip

I've seen various "recommended" chamfers for 90 degree grounded coplanar and microstrip traces. For example, or . Is there a "rule of thumb" for which type of chamber and which geometries work best ...
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1answer
40 views

Why am I getting different Voltage Losses?

The step-down transformer has a ratio of 10:1 $$P_{globe}=V_{globe}\cdot I_{globe}$$ $$P_{globe}=V_{globe}\cdot I_{globe}=\left( 2 \right)\cdot I_{globe}=4\ \mbox{W}$$ $$I_{globe}=2\; ...
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1answer
65 views

Crosstalk Question

Could somebody explain me how could I predict the crosstalk between tracks.From what I know about this are two types of crosstalk: inductive and capacitive.Inductive from what I read is the worst.For ...
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4answers
117 views

Coaxial/UTP Equalization Circuit

I have a problem with a circuit that transmitts a video signal(PAL 1.0 Vp-p) through a coaxial cable of around 200m.My problem is that the high frequency content is really attenuated by the cable.I ...
7
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1answer
156 views

What are these coils on transmission lines?

What are these coils? This was asked by doetoe in this physics.stackexchange Question Where I saw them (maybe six or eight pairs) they came in pairs, always on the same two lines, and they were ...
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2answers
80 views

Issue with circuit design 10x probe

I designed a board to mux 16 inputs into a 4 channel scope using relays. I also included circuitry to replicate a 10x probe on the board. That is, I placed a 9M ohm resistor in parallel with a 1.4pF ...
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0answers
92 views

Impedance discontinuity problem at transmission line?

I am confused about how the waveform will be to the left of discontinuity. Please help me understand it better. Here is my understanding: When the unit step hits the inductive discontinuity, at ...
3
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1answer
389 views

How does a telephone hybrid transformer work?

Suppose the following circuit: I can see how an incoming signal (Kim's voice) wouldn't be coupled with the lower pair, but I can't see how an outgoing signal (Ron's voice) only goes through the ...
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2answers
66 views

Is there an order in which electricity goes off from the point of disconnection or fault?

Have watched in a lot of movies, in scenes where their is a blackout and the power is going out like lets say for a country, the going off of the lights seems to follow a specific pattern.. so i was ...
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1answer
231 views

what is shunt charging in power systems?

I am currently working with Power World Simulator. When inserting transmission lines, there is a parameter called shunt charging. What is this and what effect does it have on power loss in the line?
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2answers
111 views

How does electrical interface on multi-subscriber FDM telephone line work?

I am wondering how the electrical interface for a frequency multiplexed telephone line works. If two senders are connected to a single line, how is it that the final output stage amplifiers don't ...
0
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1answer
65 views

how remote key of popular car brand working wide range?

i did remote control for garage opener with cheap module supply with 3v coin cell battey,i got 30-40 meter range by spiral type antenna setup and got 80 meter range wipe type antenna setup. i ...
0
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1answer
53 views

What happened to the reflected wave back to source?

The setup is as followed Signal generator (50 Ohm) -> coax cable (50 Ohm) half wave length-> short circuit Of course I didn't do this because I thought this might blow up something, it's just a ...
0
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1answer
101 views

Is my current transformer rated for 11kV Tranmission line?

I'm using a current transformer to measure current on HV transmission lines. Except i'm finding it difficult to find a split core CT that will be rated for 11kV. My CT that i'm looking at is the ...
2
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1answer
313 views

transmission lines voltage drop

When trying to explain the need for high voltage in transmission lines, I came across a formula in one of my old courses: A transmission line is considered, and between the generator end and the load ...
0
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1answer
65 views

How do I learn to design a 50Ω coaxial interconnection/interface? [closed]

I've designed an electronic load for testing power supplies (circuit and photo in this post: Designing a *linear* MOSFET driver stage). The load can be controlled (programmed) using an arbitrary ...
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1answer
53 views

Tranmission line equations when initial conditions are not zero

A high voltage DC line is in steady state sufficiently long time after applying 1 MV at the input terminals through a DC voltage source of 30 ohm impedance with an open circuit at the load end. The ...