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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HVDC HAS MORE ADVANTAGES OVER AC,SO WHY WE CAN'T USE FOR HIGH POWER TRANSMISSION LINE? [on hold]

friend, i read dc power supply is good and have over advantages on ac supply. but ,in now day we can't use high dc supply, i read we can't generate high dc power. but,we can convert high ac power ...
0
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3answers
44 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
35 views

How is data transmitted on different media?

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
90 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. ...
0
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1answer
39 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
38 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 ...
0
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1answer
51 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 ...
2
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2answers
50 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
52 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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57 views

What is flashover in transmission lines?

I came across the following sentence in my electronic design book: "The power-handling ability of a transmission line is limited by flashover." There is not explanation in the book and I can't seem ...
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1answer
34 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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2answers
58 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
78 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
84 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
votes
2answers
547 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
59 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
116 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
61 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
35 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 ...
1
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1answer
39 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
58 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 ...
1
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4answers
95 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
149 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 ...
2
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2answers
69 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
84 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
215 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
132 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
95 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
53 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
49 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
80 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
135 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
57 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
50 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 ...
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2answers
111 views

Building a distributed low-pass filter with cutoff frequency of 1hz but the highest frequency of 10^13 hz

How does one build a distributed low-pass filter with cutoff frequency of 1hz and highest frequency of 10^13hz (or arbitrarily high)? In case of lumped circuits, this is easy to do, but in case of ...
2
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1answer
61 views

Cell phone bluetooth range

I've got this phone I'm doing some range testing with...Namely, a Samsung S5 with the latest firmware and I'm testing the WLAN/Bluetooth radio. This phone has unbelievable range...but, when I replace ...
2
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1answer
66 views

Where to Measure S11 with a VNA

I have someone else's design that I have been asked to choose matching components for. The antenna is a chip antenna and the filter is a band pass SAW filter in a single package. The SAW filter is ...
8
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5answers
591 views

Why does reflection only applies to transmission lines?

Why does the concept of wave reflection seem to only apply to transmission lines? For example, for a simple circuit with two resistances R1 = 50\$\Omega\$ and R2 = 75\$\Omega\$, is the voltage wave ...
0
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1answer
60 views

Mulitple open-circuit transmission lines

I'm using a single SPI microcontroller to talk to about 10 boards. Of course, only one of them is actively listening at a time, using chip select (for the unfamiliar, when chip select is high, the SPI ...
1
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40 views

antenna matching with lumped elements

Is there any resources online that describe how to match antenna elements to a TX line with a lumped element matching network? I've got a 50 ohm load and a TX line that i'm trying to match to a ...
0
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1answer
64 views

Can I tell the voltage of High Power Transmission lines by its Type?

I am moving to Foster City, CA and am looking at an apartment about 550 feet from these power lines: ...
2
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1answer
71 views

S11 all on the outside of the Smith Chart

How should someone conclude what's going on on a TX line that has a Smith Chart that goes around and around the outside? I've reworked a board and expected to see a curve pass close to (0,0), but what ...
0
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1answer
106 views

Shunt capacitor as discontinuity in transmission line

As in the following circuit simulate this circuit – Schematic created using CircuitLab suppose that an infinite transmission line (with characteristic impedance \$ Z_0 \$) ends upon a ...
0
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0answers
32 views

Calculating DC resistance from p.u. impedance

I need to calculate or approximate the DC resistance of a 208.5 km overhead line which has the following information: impedance per unit on 100 MVA base: R = 0.004 X = 0.047 B = 1.049 Is it even ...
0
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1answer
212 views

Transmission line: Why do longer traces cause signal reflections?

As the question says, I want to know why do longer traces/longer lengths of non-terminated signals of the PCB cause reflections and not the short length ones? I am ignoring the negligible amount of ...
0
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2answers
70 views

How to make proper copper trace transmission line calculations using wCalc?

Oli Glaser gave a fantastic answer to a question regarding termination resistors: Termination resistors: are they needed? I am trying to replicate his wCalc and SPICE simulation calculations for ...
8
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4answers
1k views

Does current flow on an open transmission line?

Please take a moment to look at the diagram below: The question is if the lightbulb will momentarily flash when the switch is closed. I think it will but I get the feeling I am wrong. The reason ...
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1answer
72 views

Confused regarding standing waves on transmission line

I am currently learning about transmission lines form an online book hosted by a website called “All About Circuits”. If anyone is interested, the particular chapter I am currently reading can be ...
2
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1answer
113 views

Very odd open-drain output design

I ran across a open-drain design and am baffled by the resistor between the nFET source and ground. There are only two purposes that I see it could serve. 1) It's series source termination, matching ...