Ads
related to: active loop antenna shortwaveebay.com has been visited by 1M+ users in the past month
Search results
Results from the WOW.Com Content Network
Self-resonant loop antennas for so-called "short" wave frequencies are relatively large, with a perimeter just greater than the intended wavelength of operation, hence for circular loops diameters between roughly 175 feet (53 m) at the largest, around 1.8 MHz. At higher frequencies their sizes become smaller, falling to a diameter of about 11 ...
Curtain arrays were originally developed during the 1920s and 1930s when there was a lot of experimentation with long distance shortwave broadcasting. The underlying concept was to achieve improvements in gain and/or directionality over the simple dipole antenna, possibly by folding one or more dipoles into a smaller physical space, or to arrange multiple dipoles such that their radiation ...
The nulls in the radiation pattern of small receiving loops and ferrite core antennas are bi-directional, and are much sharper than the directions of maximum power of either loop or of linear antennas, and even most beam antennas; the null directionality of small loops is comparable to the maximal directionality of large dish antennas (aperture ...
An ideal “broadband” shortwave antenna would work continuously across much of, if not all of, the shortwave spectrum with good radiation efficiency and minimal compromise of the radiation pattern. Most practical broadband antennas compromise on one of the above: Either they only work on a few relatively narrow slices of the HF radio ...
An antenna array consisting of two such antennas, one above the other and driven in phase has a gain of up to 17 dBi. Being log-periodic, the antenna's main characteristics ( radiation pattern , gain, driving point impedance ) are almost constant over its entire frequency range, with the match to a 300 Ω feed line achieving a standing wave ...
Active antenna; ADA (smart antenna) ... Loop antenna; Low-probability-of-intercept radar ... Self-complementary antenna; Short backfire antenna; Shortwave relay station;
The AT&T receiving Beverage antenna (left) and radio receiver (right) at Houlton, Maine, used for transatlantic telephone calls, from a 1920s magazine. The Beverage antenna or "wave antenna" is a long-wire receiving antenna mainly used in the low frequency and medium frequency radio bands, invented by Harold H. Beverage in 1921. [1]
A 20-meter-long T²FD antenna, covering the 5-30 MHz band. The Tilted Terminated Folded Dipole (T²FD, T2FD, or TTFD) or Balanced Termination, Folded Dipole (BTFD) - also known as W3HH antenna - is a general-purpose shortwave antenna developed in the late 1940s by the United States Navy.
Ads
related to: active loop antenna shortwaveebay.com has been visited by 1M+ users in the past month