Questions tagged [coaxial]
50 questions
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How are unbalanced coaxial cables used for broadcasting TV signals without any problems?
As far as I know, in telephony STP or twisted pair cables are used. This creates balanced line impedances which is useful to mitigate for common mode related interference.
So using balanced cables in telephony and in audio is crucial to get rid of…
user1245
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What does "mode-free" mean, in the context of coaxial connectors?
I've seen a number of coaxial connectors claimed to be rated for "mode-free operation up to (whatever) GHz"--but after much searching, I can't seem to find any definition of "mode-free".
(source)
(source)
What does "mode-free" mean in this…
Hearth
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Why are coaxial cables typically faster/longer than twisted pairs?
I'm having trouble understand why coaxial cables tend to have higher bandwidth compared to twisted pairs. I couldn't find any source explaining why, they just mention the fact.
For instance:
"In comparisons between coax vs twisted pair, coaxial…
Essam
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Can two 802.11n devices communicate via a coaxial cable?
Coaxial cables with RP-SMA connectors are often used as extensions for external antennas / with software defined radios.
What would happen if I were to connect two access points (wifi chips, via their antenna ports) using a coaxial cable? Would they…
Geosearchef
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7
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Why did CATV standarize in 75 ohms and everyone else in 50?
All of the CATV industry runs on 75 ohm systems, while most of the rest of the radio world uses 50 ohms.
Why was this standard chosen?
I was wondering this because good quality RG6 cable can be obtained everywhere for very little, compared to…
hjf
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Can someone explain me these waveforms?
During this experiment, I connected a 10m coaxial cable to pulse generator and at the load end I connected capacitor and inductor one by one, I got these waveforms. Can someone explain me the the reflection?
Jaimin PARMAR
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How is the center pin supported in air-filled coaxial cables?
In SMA cables, the PTFE dielectric supports the center pin through the length of cable.
How is the center pin supported in air-filled cables? E.g., 3.5mm, 2.9mm, K-connector, 1.8mm, V-connector, etc. I assume that there must be disks of dielectric…
qtc0
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Effect of small length impedance discontinuity in a transmission line
Consider this arrangement of a radio, a long coax cable, a small length of "random" cable and an antenna. The radio, the coax and the antenna all have the same impedance, but the random cable is impedance mismatched.
How this short length of…
Berk7871
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2
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Is an (n+1/4) wavelength transmission line impedance transformer comparable to a 1/4 wavelength line of the same composition?
I use coaxial transmission line transformers for simple power splitting and combining networks. This is for connecting multiple resonant antennas in array configurations. It's a standard technique that uses a 1/4 wavelength section of coax to match…
Captain Kirchhoff
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1
vote
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What energy/fields if any is generated when radio frequency is passed through a coaxial cable?
I am new here. Just had a question wondering if someone could answer.
Let's say I have a generator that can generate RF and send it through a cable (coaxial) if I attached the end of that wire to a flat aluminum plate of 4'x4' by 1/8"…
Longschool
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When does one have to take cable capacitance into consideration?
When feeding an RF signal to a coaxial transmission line, when do you have to take into consideration the capacitance of the cable? I am working with a 36 MHz signal. The total cable length is ~3 ft (RG316 with SMA connectors).
The source and load…
D. Zambrano
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vote
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Coaxial Transceiver - HF Signal & LF Signal on same cable
I have a project which needs a analog video signal & some control data sent on a coaxial cable, I came up with some ideas and I asked about it and some interesting answers were received (Multi "Master "Coaxial Driver Design).
Since then, I created…
Stefan Merfu
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Attenuation for high frequency when using coaxial cable
Can someone tell me why high frequencies (1 MHz sine signals) are getting attenuated in the below case.
I have a function generator with 600 Ω output impedence. I connect this output to a digitiser channel input of input resistance 1 MΩ. I connect…
jerryvdk
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vote
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How can I match a transmission line impedance on the source side?
Suppose that I want to transmit a signal by a coaxial cable to a high-impedance load.
The signal is a single-ended TTL (3.3V) single square impulse from an FPGA output. The package of the FPGA is LQFP-144. The coaxial cable is a 50-ohm RG-174. The…
Arseniy
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Coaxial Connector Termination
I am studying microwave engineering at university, but I never had a possibility to try to manufacture anything that I have been learned in my courses.
So I have decided to try it by myself. I have chosen a directional bridge at 10 GHz and I have…
Humphrey Appleby
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