Transmission Definition and 708 Threads

Dear All I am hoping for some insight into a transmission line problem I have been experiencing. I am quite inexperienced and unqualified in this area so if I am not clear please let me know. In wiring loom assemblies my employer offers there is a twisted transmission pair. The...

Hi! I would like to construct a digital circuit as like how computer transmit data. My problem is how can I make start bit and stop bit for my 7 bits data?and how can the receiver knows that that is start bit and not the data?(I confuse at this part) While sending data, how can I...

Hello, As far as I understand, a transmission line is simply a wave-guide for TEM modes. If the waves are propagating in the z direction so Hz=Ez=0. How does this fact leads to the conclusion that in any transverse plane (xy plane) the fields are conservative? Thanks a lot.

Hi, In the study of the greenhouse effect, I know for a fact that short wavelength radiation pass through a glass container and heat up its contents. When its contents get hot, they will re-emit longer wavelength (and hence lower energies) radiation, which will then be unable to pass through...

Hi Guys, I looked so hard on the net, trying to understand something that I am struggling with for the whole day, but I ended up frustrated. I am working on my design project and was assigned a part conecnred with antennas, I am using the Antenna Theory Analysis and Design by Balanis to...

Hi friends, I've calculated the transmission spectrum of ideal carbon nanotubes for various applied voltages on them. I obtained the transmission spectra shown below for various bias voltages. However, I could not interpret why the transmission spectra changes so much with the bias voltage...

The reason given for the transmission of power by way of ac rather than by dc is that the ac voltage can be stepped up so that the current can be proportionately reduced. In that case the power loss is calculated by using the formula I^2 R. But my long standing doubt is how the resistance of the...

For example , optical carrier in the infra red region can provide higher capacity than microwave.

Homework Statement I need to calculate the frequency which the receivers should be tuned to too receive one another frequency. Both are transmitting at a frequency of 17.5 MHz. I know the answer should be 54.0MHz. Homework Equations Unsure The Attempt at a Solution Unsure of how...

Dear Physics Forums Users, I have a Bachelor of Science degree on Physics and Applied Mathematics, currently on the way out of a masters in EE. As a graduation project, I chose wireless power transmission as the project topic. I found two wireless transmission schemes that got some...

I am working on tight binding formulation of CNTs. The transmission function T(E), which is the trace of the product of the lead self energies and the retarded and advanced green's function. This value is a complex entity. T(E) needs to be calculated at different energy levels and then...

Homework Statement A transmission line has the following properties: L_{0} = 1 mHm^{-1} C_{0} = 10 \mu F m^{-1} R_{0} = 10 \Omega m^{-1} G_{0} = 0 \Omega^{-1} m^{-1} That is, inductance per meter, capacitance per metre etc. The line is 10m long. The problem is to find the...

Asmall power plant produces a voltage of 6.0kV and a current of 150A. The voltage is stepped up to 240kV by a transformer before being sent to a substation. The resistance of the transmission line between the power plant and the substation is 75 ohm. How much is the current flowing in the...

Edit: My question is better expressed in my next post so ignore this post. Homework Statement A power station delivers 890 kW of power at 12 kV to a factory through wires with total resistance 5.0 \Omega How much less power is wasted if the electricity is delivered at 50 kV rather than 12 kV...

I have a very small signal coming from a thermocouple \mu V \mathrm{to}\, nV range, which gets drowned in noise when I transmit it via a 2m BNC cable, even the lock in runs into problems. I am about to amplify it at the source, and while I am at it, I will try to do a few more tricks...

I understand that reflected waves on a transmission line are a result of the constraints of Ohm's Law and Kirchhoff's Law at the transition points. However, I'm having trouble visualizing the physical cause for this. What is actually causing the electrons to flow in the opposite direction...

How can people get internet access through their power lines? Wouldn't all the transformers act as low pass filters and destroy your carrier signal? Also, with things being turned on and off constently, wouldn't it be too noisy?

I am a student. We are working on a design project, and long story short, we need to transmit power on the moon. We have decided on a gear system but still need to transmit from the gear output to the axles, and were considering v-belts. Does a belt exist that could operate in such extreme...

I'm supposed to write a brief essay response to this question on my unit exam, and I don't exactly understand it. Please explain it to me, and then I can appropriately write the short essay. Thanks! Homework Statement "The energy companies use step-up transformers to send high voltage...

Homework Statement A transmission line consists of a cylindrical conductor of radius r at a distance d in air from a conducting plane (r >>d). Derive the capacitance per unit length C and the inductance per unit length L and check that 1/sqrt(LC) = c. Homework Equations The...

Hi all, The relation between the magnitudes of the incident, reflected and transmitted waves are obtained using Fresnel coefficients. If a field moves from air to a more denser medium, which field should have a greater magnitude (reflected or transmitted)? I thought that it would be the...

My understanding is that the capacitance of a typical transmission line will increase proportionally to it's length. So in the case of a simple passive LPF circuit, consisting of just the LPF and the transmission line to the load (of infinite impedance), this would in turn mean the cut-off...

If you have a stick and push it from one end, the whole stick moves instantly. You have given the other end of the stick kinetic energy. So doesn't this mean that you have transmitted energy at an infinite rate, rather than at or below the speed of light?

Hi all, I was reading "Geometrical Optics Reflected Fields" chapter from "Introduction to Uniform Geometrical Theory of Diffraction" textbook. The author assumed that the surface is perfectly conducting and therefore he only considered the reflected waves. He derived a formula for the...

A transmission diffraction grating with 520 lines/mm is used to study the line spec- trum of the light produced by a hydrogen discharge tube. The grating is 1.6 m from the source (a hole at the center of the meter stick). An observer sees the first-order red line at a distance yred =...

I want to transmit digital signals over an existing electrical network. Can someone give me an idea of how to go about it?

hiiii... i needed some help in collecting some articles related to automatic transmission...i need the basic idea of it,and comparison with manual transmission...

If a single conductor in a transmission line dissipates 6,000kWh of energy over a 24 hour period during which time the current in the conductor was 100 amps. What is the resistance in the conductor. So could I just conver the kWh of energy to kW by dividing by 24 hours...than just use ohms...

Homework Statement A river canyon is 147 m across as shown in Figure P.32. You are located on the river surface and clap your hands once to generate a brief acoustic pulse. You detect a time interval of 0.407 s between the twin echoes recorded on tape, analyzed when back home (?) in a...

I wonder what's the best efficiency that's possible to achieve with a continously variable transmission. I've googled a lot and can't find anything useful (with useful i mean an approximate value in [%]). thanks.

If I was to measure the transmission of light through a coated piece of glass(with a coating designed to scatter light). Do I expect the optical transmission to be different if the light is incident upon the coated side compared to if the light is incident on the uncoated side and exits through...

The GPS (Global Positioning System) satellites are approximately 5.18 m across and transmit two low-power signals, one of which is at 1575.42 MHz (in the UHF band). In a series of laboratory tests on the satellite, you put two 1575.42 MHz UHF transmitters at opposite ends of the satellite. These...

Homework Statement Design a dc transmission line that can transmit 225 MW of electricity 185 km with only a 2.0% loss. The wires are to be made of aluminum and the voltage is 660 kV. 2. Homework Equations P= IV = I^2 * R R= p(L/A) Power loss = Pf - Pi Attempt at a solution I worked through...

Hi, Basically I'm doing a report on a logic analyser lab - I realize this isn't the homework section - and I'm looking to extend a basic discussion on synchronous/asynchronous data transmission to analysis of pumped and source-synchronous transmission...

I am studying EM wave and transmission lines. I see both derive equations for propagation constant \gamma: Plane wave velocity is 1/\sqrt{\mu\epsilon} and \eta = \sqrt{\mu/\epsilon} Transmission line velocity is 1/\sqrt{LC} and Z0=\sqrt{L/C}. From that the book just to say the velocity...

Homework Statement A beam of electrons of KE = 100 eV is incident from the left on a barrier which is 200 eV high and 10 nm wide. If the momentum spread is sufficiently narrow, then a simple plane wave is a good approximation. Recall that the mass of an electron is mc2 = 511 keV. ....._____...

Homework Statement A power station delivers 890 kW of power at 12 kV to a factory through wires with total resistance 5.0 \Omega. How much less power is wasted if the electricity is delivered at 50 kV rather than 12 kV? Homework Equations eq-1) P = IV eq-2) P = I2R Ohm's Law...

Homework Statement The aperture has vertical opaque strips of width, a, separated by open spaces of width 2a. The width of the overall aperture is L = 19a. a) Write a transmission function for this aperture. b) What would the field distribution be, at a plane in the Fraunhofer zone, if the...

Hello everybody, I have a question and I am wondering if you can help me find an answer. The problem I am trying to figure out is: I have 400 miles of 345 kV transmission line. An outage happened twice in two different locations on the line caused by two different lightning strikes, a 35kA...

Homework Statement Why is serial data transmission preferred over parallel transmission when needing to transmit data over vast distances? Homework Equations The Attempt at a Solution I think this has many different reasons...but I'm trying to pinpoint important ones. -I think...

We are constantly told at school that in order to reduce power loss in overhead cables, high voltages and low currents are used as P = I squared R. This seems to make sense until you substitute I=V/R into P=VI and get P = V squared / R. Now if voltage is increased in the cable, and resistance...

Ok when they taught me about this they kept saying the power loss = I2*R Well isn't the power loss also = V2 / R Now before you give me the regular answer of "this V is not the same as this V", i understand. However, from what i know from the voltage divider rule is that the V across the...

I'm currently doing a lab on pulses in cables. The instructions describe the transmission line as a series of parallel lc circuits that transmit the pulse back and forth along the line, but I'm not sure I understand exactly how it works. I understand how an individual lc circuit works, but I'm...

I am studying Poynting vectors. I run into question that I don't see any good explanation in all the books I have. All the books claimed E_{(z,t)} =E_{(z=0)} Re[e_{j(wt-\beta z)} + \Gamma e_{j(wt+\beta z)}] But sinse E0 is complex so this is what I have and is not equal to what the...

Hi I am trying to calculate impedance in a line transmission but can't seem to figure it out :( i have so far undertood that it is calculated by zo = R+jwL/G+jwC The values i have found so far to help me with the task are: R =100 ohms L=225 micro henry C = 9.3 Nano farads G = 0.01 S...

Okay I'm just very confused by a statement in my textbook and could use some clarification. It says that power is transmitted at high voltages in order to minimize heat energy loss. It then says "it must be noted that this is because the higher the voltage is, the lower the current". Well...

I am considering the idea of making a small scale wind turbine for my final year B.Tech project. I have run into a roadblock, I have to maintain the generator at a relatively constant speed. I was thinking of 2 parallel shafts one from the Turbine blades coupled via a CVT to the shaft to the...

Problem : a) A good sized English book has about 100000 words. If an average English word is six characters long and each character needs 1 byte, show that the book can be stored in 600 kbyte of memory and show that the text takes nearly 5 seconds to be transmitted at 1 Mbit s-¹. Show that it...

Light known to be polarized in the horizontal direction is incident on a polarizing sheet. It is observed that only 15 percent of the intensity of the incident light is transmitted through the sheet. What angle does the transmission axis of the sheet make with the horizontal? I am not quite...

I think pretty much everybody knows the length of the transmission line should be less than the wave length of the RF signal. How do you explain it to some one who is not from engineering background. I myself can't get it some times. Say for example the wavelength of a wave is 2" =...