New answers tagged antenna-construction
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I see knots being used for desktop lamps, after the wire enters the lamp, with stranded-wire. #1.) The more sharp the bend, the more you stress the wire and prepare it for breakage. As long as it's just one time, and no repeats, no bending and unbending, you should be fine. #2.) If you want to be safer, slip a little heat-shrink on first, tie the knot in the ...
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I would refrain from knotting antenna wire meant for a long-term installation. Knots in rope weaken the rope by 20% to 60% (source). I don't know of any research on knots in antenna wire, whether kevlar-reinforced or "knot" (sorry, couldn't resist the pun), but it seems reasonable to expect that tying a knot in antenna wire weakens it. You might ...
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Generally, stranded wire used for antennas is fine to knot. However, thin solid wire that is knotted or kinked can develop a weak spot that can break under tension.
You would not, for example, want to knot load bearing cable used as guy wire, even at the tips. Instead, you can use a wire thimble (selected as appropriate for wire diameter and alloy).
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It should be fine. Stranded wire will take that kind of bending easily. If you were to tie and untie the knot many times you might eventually weaken and break some of the strands, but if it's tied once and left in position, it won't create so much stress.
If you're worried, of course, there are alternatives — you could slide a small plastic bead onto the ...
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If you need calibrated output then you probably won't be able to do it. That's why they are so expensive. It's like a \$20 SDR dongle versus a \$2,000 spectrum analyzer, with the most notable difference being that the spectrum analyzer is calibrated and tells you how much power is at each frequency.
If you don't need calibrated output and just want to get a ...
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Years ago I used a simulation like this one for the same purpose.
The antenna you refer to is a tuned antenna, so it is not wideband. The antenna that I made is a wideband, really flat response (conversion from field strength to output voltage is frequency-independent).
Conclusion: the difficulty is the design of the low-noise amplifier. Depending on what ...
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I know that the gap between the wall and the antenna mast that would be created using the wall mounts you mention is not for lightning damage prevention purposes. If a bolt of lightning can travel hundreds of meters from a cloud to the ground, another half-meter of air between a mast and a building won't be much of a deterrent, especially when the bolt ...
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