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Chameleon P-LOOP 2.0

Hello operators This is a video introduction to the Chameleon P-LOOP 2.0 magnetic loop antenna. This is the latest revision in Chameleons Man-Portable Magnetic Loop HF Antenna line-up for amateur radio. Today I am operating from the portable ham shack, qrp portable, with the Yaesu FT-817ND. The Chameleon P-LOOP 2.0 is a natural evolution in man-portable magnetic loop antennas. It's lightweight, has a small breakdown size, and can be easily configured for rapid deployment, or maximum efficiency. Magnetic loop antenna (also known as small transmitting/receiving loops) are small compared to other antennas for the same wavelength. A magnetic loop is one in which the current amplitude is constant round the circumference, and it is therefore small enough to avoid a significant standing wave in the current distribution. Small transmitting loops are typically smaller than 1/4 wavelength in circumference at the intended frequency of operation. Since full-size antennas for shortwave communication can be very large -- sometimes several hundred meters in size -- the loop's ability to operate with smaller size gives it some advantages, especially for portable ham radio and military use. Conceptually, the magnetic loop can be thought of as a high Q tank circuit having very large diameter to length ratio to facilitate the magnetic "leakage" that makes it effective as an antenna. Although we have published homebrew magnetic loop antenna plans on the channel, some operators want a well built magnetic loop antenna, they can rely on for ham radio portable digital work. The main advantage of the antenna is its compact size. These antennas are usually operated close to ground and therefore produce high-angle radiation at the lower frequencies, which is well suited to NVIS (near-vertical incidence skywave) propagation. Usually a capacitor is used to "enlarge" the antenna by tuning it to resonance in a parallel L-C circuit. This method causes the narrow bandwidth of the antenna (high Q) limits operation to a narrow frequency range. A high Q is advantageous, since tuned magnetic loops work within a narrow frequency range, when used for reception they reject noise produced in the receiver from intermodulation products. This reduces the noise level as compared with wider-bandwidth antennas. A further advantage of magnetic loops used for receiving is that they respond to the magnetic-field component of the arriving signal; locally generated rf noise (within 1/6 wavelength) has a generally weak magnetic component so the noise tends to be rejected. This effect is more marked at lower frequencies. I hope you enjoy the video de oh8stn    • Chameleon P-LOOP 2.0   Disclosure: Some of the links above are affiliate links. This means that, at zero cost to you, I will earn an commission if you click through the link and finalize a purchase.