The transmission-line tag has no wiki summary.
6
votes
4answers
134 views
Can we measure reflected power in a transmission line?
This is a question related to radio transmission, I hope this is the proper forum to ask it. It relates to transmission lines connecting a radio transmitter to its antenna.
In his book "Reflections", ...
0
votes
2answers
60 views
How does less cable impedance, source/termination impedance, lead to longer cable length for higher data rates?
This question is about high speed digital transmission on a transmission line,
I need to know about how does the
(1) impedance of the transmission line and the
(2) source impedance and
(3) ...
26
votes
2answers
454 views
If we could start our electrical grid from scratch with today's technology, which would be the most efficient choice? AC or DC?
Lately, I’ve been reading about the many advantages of HVDC transmission systems for long distance transmission, undersea links, and others. The historical reason of why AC was picked over DC was ...
16
votes
3answers
335 views
Transmission line reflection. I would like a non-mathematical explanation
I am a licensed radio amateur, and find bewildering the many different explanations, which range from folksy urban myth to Maxwell-Heaviside Equations, of what happens at the termination of a ...
4
votes
1answer
120 views
Cable Splitter Loss and Impedance Matching
From my memory, cable splitters (such as for splitting a cable tv coax cable into two televisions) provide impedance matching to prevent signal reflections, etc.
If one 50 Ohm line is split into two ...
0
votes
1answer
96 views
What is a good tolerance for impedance matching or how to calculate losses?
If you build a microstrip on a silcon wafer, connected by picoprobes via SMA connector and cables to a VNA, what is actually a good match of the impedances of the cables and the waveguide. Is there a ...
3
votes
1answer
151 views
How does the addition of a bias-t circuit affect the impedance of a transmission line?
I've got a GPS circuit where the antenna is connected directly to the GPS receiver via a coplanar waveguide designed for an impedance of 50ohms. Unfortunately, I neglected to add the bias-t circuit ...
2
votes
1answer
118 views
Will an oscillator be able to drive a transmission line
I want to build a soil moisture measurement probe based on this idea:
An oscillator feeds a transmission line burried in a soil via a termination resistor R1, XOR gate acts as a phase shift ...
3
votes
3answers
424 views
How does an swr meter directional coupler work?
How does the directional coupler in an swr meter work? How are the forward and reflected waves separated out from the standing wave on the feeder?
I would like an answer in terms of sine (or cosine) ...
8
votes
3answers
500 views
How is rise time related to bandwidth of the signal?
Say, I want to limit the rise time of my digital signal edges to avoid dealing with transmission line effects.
How do I determine the maximum frequency of harmonics in my signal knowing that my rise ...
0
votes
2answers
116 views
Multiple level signal transmission
I'm interested in increasing the transmission rate over Cat5 for a personal project. (Cat5/5e/6 will be chosen because of it's properties and obtainability but will not be used in the standard way)
...
1
vote
2answers
189 views
Why is impedance represented as a complex number?
Let me know one thing. Why is impedance represented by a complex number when considering loss?
Usually it is said that imaginary part is because of loss. Is it True?
If it is true then does that ...
13
votes
2answers
419 views
Why not use a ferrite bead around an RS-232 cable?
This is from the instruction manual of a printer:
As you can see, one is not supposed to wrap the supplied bead around the serial cable. What is the reason for this?
0
votes
0answers
69 views
Formula to calculate filter frequency of cable based on input and output impedance
Has anybody come across a formula to calculate Fc based on the capacitance of a cable, using the output impedance and input impedance of the preamp and amp respectively.
5
votes
3answers
437 views
Long transmission line inductance with SPI
I have a PCI 5V GPIO card which bit-bangs SPI over a 10-foot cable. The SPI clock is running at 800Khz. The cable connects to a board and the SPI lines feed directly into the SPI IC's. I know SPI is a ...
-1
votes
1answer
125 views
Power Grid in depth explanation [closed]
I am looking for links, books, papers, documents or any other reference type that allows me to get a very in depth overview of the power transmission and distribution network (preferably of the UK). ...
2
votes
1answer
113 views
Scattering matrix Transmission Matrix lasers
I would like to ask if anyone can suggest me a good tutorial about Scattering and transmission matrices for lasers.
I am really struggling with some issues and the majority of the literature analyses ...
0
votes
2answers
388 views
source/output resistance
I was wondering why many generators ect. have 50 ohm output resistance.
Before you answer here is what I know:
Many transmission lines are 50 ohm, and terminated with a 50 ohms load to get maximum ...
4
votes
1answer
132 views
Interconnect capacitance and speed of data transmission?
Is the interconnect capacitance in a transmission cable is having an impact on the maximum data transmitting rate ?
Or is it only producing "crosstalk" ?
1
vote
1answer
136 views
Using an eye diagram for dynamic equalization?
I was just watching this video Tutorial on Passive Filters, Data Transmission and Equalization. In the video he shows how one can use the size of the opening in the eye pattern as a way to measure the ...
3
votes
2answers
236 views
Why does the ISDN S0-Bus require terminating resistors?
It is a well-known fact that ISDN S0-Bus must be terminated with 100ohm resistors to match the transmission line. This is the case even for everyday household installation with cable runs shorter than ...
2
votes
1answer
259 views
Terminating Transmission Lines with a Resistor
I have a large, but slow, SPI bus comprising of 8 devices. The frequency of operation is 2 MHz. As I understand, I need to ensure that the bus lines are properly terminated or reflections may cause ...
7
votes
3answers
675 views
Meaning of balanced transmission line?
Simple question, what does it mean to have a transmission line (RS-485 in my case) balanced vs unbalanced?
3
votes
4answers
705 views
How to terminate 50 ohm transmission line without drawing DC
I am sending a 10 MB/sec digital data stream by amplitude moduating a infrared quantum cascade laser. The laser requires a hefty bias of about half an amp (which drops about 8.5 volts across the ...
7
votes
2answers
717 views
Is paying extra for “Controlled Impedance” boards necessary?
I'm doing a bit of RF PCB design, and one of the things that caught my eye is the "Controlled Impedance" option. Checking more boxes always costs more, so I want to know if this is worth the extra ...
4
votes
3answers
212 views
Transmission line
I'm currently testing a design, and using two small wires to connect an oscillator with a frequency counter (both are small circuits I have build).
So here is a question, when designing RF and ...
3
votes
3answers
679 views
Transmission line simulation (physical)
I need to be able to simulate communications with a sensor device over a large length of wire (0-10km). This is for quite low-speed comms (10khz max, usually 1-2khz though). This would be FSK... but ...
6
votes
5answers
1k views
Is passive GPS retransmission possible?
Is it possible to passively pipe GPS satellite signals indoors via a waveguide, or 2 antennas connected by a coax? If so, with what type of waveguide, antennas, coax, etc. should I try and ...
5
votes
2answers
991 views
Transmission Line and capacitive effect
I am driving a digital pin with a 10Mhz signal. At the pin, the signal's rise time is slewed to 35us such that the signal is no longer a pulse but a triangular waveform that does not reach the full ...
