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2 votes
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How can I simulate an RF signal as received by an antenna in LTspice?

Yes, to all, with the caveat that (4) will take a very long time as transient simulation proceeds incrementally, as discussed in another recent question. And consequently might not be very accurate (...
Tim Williams's user avatar
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1 vote

How can I model FM antenna in SPICE?

Modeling an antenna purely with spice is not exactly possible to my knowledge. You can use a third party software (MMANA-gal software: http://gal-ana.de/basicmm/en/) to model your antenna and from ...
DRF's user avatar
  • 536
1 vote

Maximizing magnitude of fields created by an antenna

If the loop antenna is much smaller then the wavelength, it is commonly regarded to as an inductor. It acts more like an inductor. Yes, you need maximum current fir maximum magnetic field, but the ...
ursusd8's user avatar
  • 414
1 vote

12 channel remote control: 4-pin IC for 12 buttons: How?

When you look at the logic table on P.2 of the datasheet, you'll see that for certain combinations of pins getting pulled high, you get specific data output. You can pull multiple pins high with a ...
Marcus Müller's user avatar
2 votes

12 channel remote control: 4-pin IC for 12 buttons: How?

The 4 inputs are in binary. When you press any button, it both sets these 4 inputs to some value and powers the chip. The diodes are used to set the 4 input pins based on which button you pressed. ...
Justme's user avatar
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0 votes

MICRF112: loop vs monopole antenna

No, the matching network component values will need to be reevaluated if you want maximum efficiency. The datasheet also provides component values to match the IC to a 50 ohm load, and if you use ...
Mark Leavitt's user avatar
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0 votes

Electrically long loop antenna with homogenous near B field inside antenna loop

Putting these loop coils in parallel is equivalent to adding more windings. You could put them some distance apart but that would reduce the constructive interference. Maybe there is a sweet spot. ...
Carsten's user avatar
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7 votes
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Can we catch signals from a cellphone using an external device?

The first two? Yes. The third one? Yes, you can search for patterns, and you'll find them, because not all the information is encrypted. The encrypted information probably won't have patterns, or if ...
BeB00's user avatar
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1 vote
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Single stub matching of loop antenna at 4.2 GHz

What does the "BNC Tee" do? Aside from the fact that 4.2 GHz and BNC are not usually combined, on this hinges the whole idea. Also, note that most BNC tees that exist in the world are from ...
Marcus Müller's user avatar
0 votes

Matlab simulation of PCB IFA

The y axis of these graphs appears to be multiplied by 10e-3 and is in dB. Therefore, it basically is equivalent to being 0 dB across the entire bandwidth, which is pure reflection, so neither of ...
Matthew Kunkle's user avatar
1 vote

Question About Utility Company Antenna Power/Radiation Concerns

That's not a lot of power, 2 W is half what a typical two-way portable radio would output. If the radiated power is 15 W that means that the antenna would have gain, roughly $$ Gain = 10\times log(15~...
GodJihyo's user avatar
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1 vote
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Are these antennas interchangeable?

It's hard to say just by looking. An antenna is matched to a specific device, not only by frequency, but by impedance. If the Lilygo-T-RelayS3 has a series inductor (base loading coil) to compensate ...
DrMoishe Pippik's user avatar
0 votes
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Question About Utility Company Antenna Power/Radiation Concerns

The strength of a radiated signal falls off according to the square of the distance. At the distance of 500 ft, this is greatly below any concern about human safety. Aside from 15 W being fairly low ...
DrMoishe Pippik's user avatar
5 votes

If electromagnetic waves are indeed created by a changing electric and magnetic field, then why don't we see magnet based antennas?

You could indeed make an EM radiator by moving a magnet -- spinning it cross-axis, say. The problem is, for the speed to be fast enough to have reasonable (or even detectable?) emissions, no known ...
Tim Williams's user avatar
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8 votes

If electromagnetic waves are indeed created by a changing electric and magnetic field, then why don't we see magnet based antennas?

We are bombarded by EM radiation from many sources. Here, from https://swling.com/blog/2016/06/steve-points-out-the-itu-r-recommendations-on-radio-noise/, is radio noise from various sources. At ...
John Doty's user avatar
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0 votes

Is it possible to design a compact antenna for detecting the presence of 50 Hz mains voltage at very short range?

I've prototyped and smart device capable of energy harvesting and measure it. It is available on GitHub here: https://github.com/aeonSolutions/Aeonlabs-Home-Automation-Smart-EMF-Shield-Curtain-for-...
Miguel Tomás's user avatar
1 vote
Accepted

Adding SMA connector to a 433 MHz remote

I believe the antenna is the rounded "M" shaped trace along the upper edge of the PCB. At it's right end is the feedpoint with an SMT part (probably a capacitor) connecting it to the rest of ...
Mark Leavitt's user avatar
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