Questions tagged [dielectric]
A dielectric is an insulator that can be polarized by applying an electric field. A common example is the use of a dielectric within a capacitor between the metallic plates to increase the surface charge.
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Would an inductor work differently under a different dielectric environment?
I am talking about these common rounded inductors with a metal core that you would find on PCBs.
Would the operation be different in, say, mineral oil vs. air? These are two different dielectric ...
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How does selecting a higher permittivity substrate in patch antenna reduce its size?
By selecting a higher permittivity substrate do we reduce the height of the antenna or we reduce the length of the patch antenna? We cannot reduce the length of the antenna as it is dependent on the ...
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Relays: What is High Contact Stability?
This TE RF relay datasheet shows the component coming in three varieties:
High Dielectric
High Contact Stability
High Current
So high-current is obvious (right?), and (correct me if I'm wrong) high ...
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Why do dielectric waveguides support hybrid modes and metallic waveguides do not?
Can anyone explain to me qualitatively why dielectric waveguides (core and infinite cladding) support hybrid modes (E_z and H_z components in the guided wave), while metallic waveguides cannot?
I am ...
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The field in a waveguide at exactly the cut-off frequency
Can anyone explain to me qualitatively, what kind of field exists inside a waveguide at EXACTLY the cut-off frequency?
I would be grateful if an explanation was given about waveguides with metalic ...
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How to increase efficiency of antenna without moving antenna far from tree?
I have designed a monopole antenna at 868MHz frequency. Now I would like to attach that antenna to the tree (wood). But, due to Why does placing an antenna far from the wood increase the efficiency of ...
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Why does placing an antenna far from the wood increase the efficiency of the antenna?
I designed a monopole antenna at 868MHz frequency. I placed wood as the surrounding material. I noticed that placing the antenna far from the wood increases the efficiency of the antenna. Can anyone ...
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Dielectric withstand test of DC powered product
I am trying to figure if our test set-up for dielectric withstand test is correct. There are two versions of the DUT (device under test), an AC powered (typical 85-264 Vrms) and DC powered type (12-...
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Ampere's Law with dielectric
I am asked to calculate the magnetic-field-strength and magnetic-flux-density for different regions inside a coaxial-cable. I found Ampere's Law for that, but it uses \$\mu_0\$ , and the coaxial-cable ...
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Following is an excerpt from a power electronics textbook. Is the statement true?
As far as I know ESR primarily depends on the type of dielectric.
eg: Al electrolytic (higher capacitance value) would have much higher ESR than ceramic (usually lower capacitance value).
Say for ...
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Capacitors: voltage-dependent capacitance?
While playing around with a capacitive power supplies, I observed some very weird behavior when passing a 60Hz sinusoidal current through a 1000V disk ceramic capacitor. The voltage curve was very ...
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How do I calculate the capacitance of a capacitive touch or water sensor?
Sensors like capacitive touch or moisture sensors are simply two traces drawn on a PCB. For example, you may check the Grove soil moisture sensor. In these types of sensors, the capacitance increases ...
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Why it can be asserted that the bottom plate takes the highest potential and the top plates takes the lowest of the capacitor?
The ideal parallel capacitor has been filled with 2 dielectrics as shown in the above diagram.
$$ V_{1} :=\text{potential at the top plate} $$
$$ V_{2} :=\text{potential at the bottom plate} $$
$$...
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When is PCB thermal destruction desirable?
In the Wikipedia page for FR-4, it contains this excerpt:
FR-4 epoxy resin systems typically employ bromine, a halogen, to
facilitate flame-resistant properties in FR-4 glass epoxy laminates.
Some ...
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Why the euclid distance between the plates of the capacitor has been doubled to find out the capacitance?
I may have been asking of an easy problem.
The problem requires to find out the capacitance.
The ideal capacitor with area of \$S\$ exists and the euclid distance between the plates is \$d\$.
The ...