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How does the rabbit ears antenna work?

You now have four threads open asking for the same information repeatedly. There is a lot of information on antennas on the net. The rabbit ears you keep showing are from the 50s era, and if you open ...
Dereck's user avatar
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Questions about radio antennas

Antennas should be resonate. For a simple wire antenna like a dipole, you want each side of the dipole to be 1/4 of a wave length or half a wave length for the entire antenna. A vertical is usually 1/...
Jim's user avatar
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3 votes

Shortwave radio antenna

However, I would like to know how the length of the wire is calculated to make it work as a shortwave antenna? It will be "just as long as possible to fit within the spool", not any ...
Marcus Müller's user avatar
2 votes

How does the rabbit ears antenna work?

Because the question is lacking specifics, this answer is lacking specifics. I need to know how much length the two whip antennas have, and how much gap should there be between them to make them work ...
webmarc's user avatar
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1 vote

Questions about radio antennas

This is way too many questions for one question, but I'll focus on one important part. For a receiving antenna, resonance is not very important at all. Below its resonant frequency, an antenna gets ...
hobbs - KC2G's user avatar
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Gap between a dipole antenna

This question isn't as meaningful as you seem to think it is. There is absolutely no value that "the gap between a dipole" "should be". If a dipole is fed conventionally (directly ...
hobbs - KC2G's user avatar
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2 votes

Running antenna parallel to steel fence: antenna effects and neighborhood RFI

First, anything metal will work. The question is always how well. For example, my 80 meter inverted vee up 40 ft worked very well. Then a 95 mph wind gust took it out. Now I have a coil antenna with a ...
Steve's user avatar
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1 vote

Running antenna parallel to steel fence: antenna effects and neighborhood RFI

Look, it will have a very negative effect you will not like. I will not sugarcoat it, assuming the antenna is not at least elevated 1/2 wavelength, and the fence acting as a reflector/director will ...
Dereck's user avatar
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0 votes

Gap between a dipole antenna

It's a relic from the 50s and 60s from a company few folks remember—the good ole days of black and White TV. Rabbit Ear antennas have not changed much. The only improvement you can make is to place an ...
Dereck's user avatar
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1 vote

Gap between a dipole antenna

The angle doesn't matter much. That isn't really a dipole antenna, but rather a related vee (or v-) antenna. Modeling of an idealized vee antenna shows nearly identical behavior from flat to 30 ...
user71659's user avatar
  • 282
0 votes

Gap between a dipole antenna

An ideal dipole has no gap at all between the two branches. Reality is that this is technically impossible to realize, and gaps that are very small compared to the wavelength don't matter (enough to ...
Marcus Müller's user avatar
2 votes
Accepted

NEC2: How do "currents" and "charges" inform antenna design and modeling?

"Charges" will tell you where the high-voltage points in your design are. If high-voltage points get too close to other parts of the structure that are at a different potential, or too close ...
hobbs - KC2G's user avatar
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3 votes

Running antenna parallel to steel fence: antenna effects and neighborhood RFI

To directly answer your question There will definitely be some kind of interaction between the fence and your proposed antenna. It's worth a shot though! Do a trial run with a temporary setup to see ...
webmarc's user avatar
  • 4,423
2 votes

Running antenna parallel to steel fence: antenna effects and neighborhood RFI

It seems like there is a conflict in wanting the antenna to be close to the fence so it isn't noticeable, yet far from the fence to reduce its effect on the antenna's radiation. Also, you would want ...
gschro's user avatar
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3 votes
Accepted

NEC2: Should I model a "tube" or just solid wire (GW) for an aluminum-tube-based antenna design?

Definitely model the yagi elements as wires. From the structure modelling guidelines: NEC2 segments should be no longer than about $0.1\lambda$ long (a bit longer is OK for straight wires with no ...
tomnexus's user avatar
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2 votes

Matching antenna at 4.2 GHz using an LC network

The way everybody else does this is to use tuned stubs of transmission line to match impedances. every inch of transmission line possesses a well-known quantity of inductance and capacitance and the ...
niels nielsen's user avatar
2 votes
Accepted

Is the TAOGLAS PCB Antenna Too Long on Purpose?

Velocity factor, probably. A transmission line with FR4 PCB as dielectric has a velocity factor of around 50% (meaning its electrical length is half its physical length). An antenna is a radiator, its ...
hobbs - KC2G's user avatar
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2 votes

Is the TAOGLAS PCB Antenna Too Long on Purpose?

I must admit I'm a bit confused by the question – the datasheet behind the link shows you the efficiency of the antenna for different frequencies (i.e., different wavelengths). That is what the ...
Marcus Müller's user avatar

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