a loop antenna having an electrically small circumference, often less than 1/10th wavelength.
Questions tagged [small-loop]
7 questions
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What does the addition of a shield to a small loop accomplish?
A small shielded loop is an antenna with a loop of wire, smaller than 1/10th of a wavelength in diameter, also surrounded by a shield. Often, they are constructed from coax. There is a gap in the shield somewhere. Feedpoint arrangements differ among…
Phil Frost - W8II
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Does a loop antenna have less susceptibility to atmospheric noise than an open ended antenna?
I always get the feeling that an antenna which has a loop for the driven element such as a folded dipole or quad will pick up less static or 'high impedance' noise than an antenna that has free ends such as a dipole or long wire. Noting that…
Andrew
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Colocated three orthogonal wire loops for lightning detection network
I'm considering building multi-turn wire loop receive antennas for a blitzortung.org lightning detection receiver. It has three separate channels for H-field antennas, operating simultaneously.
Typically, only two orthogonal loops in vertical…
Xpector
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Why does an "electrically small" antenna have narrow bandwidth?
Reading this interesting piece on magnetic loop antennas, the author explains that a magnetic loop has great efficiency even at small size, but the the price you pay is very narrow bandwidth. Why is this?
It seems counter-intuitive (and miraculous)…
bcattle
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Optimising a small magnetic loop with 1:1 SWR but little radiation
I'm trying to build a small magnetic loop for 5W on at least 40m - 20m following ideas of G4ILO's wonder loop. For this, I'm using coax with a ~2mm copper core and ~1mm spacing to the braid (see 1st image below), with braid and core connected on the…
user885
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Loop Antenna - configuration?
Due to space limitations, I'm looking at loop antenna designs. I'm starting with receive only, but hope to eventually transmit.
I've seen magnetic loops (single turn with a coupled loop) and I'm wondering: how would a second turn impact…
Alan Campbell
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Why is self-resonance important in a loop antenna?
I visited a "small loop antenna" calculator web site today and fed in my horizontal loop gepmetry, curious to see what it would say. 2" dia wire, 72' circumference, 3.935MHz. Interesting results, though it mentioned avoiding lambda/4 lengths due…
Chris K8NVH
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