EWE Antenna
yesterday, 6:00 Radio Bulgaria h Society DXers Area Requirements to antennas for radio reception DXers Area
27/03/1911 Now is the equinox and changes have begun distributing the airwaves. This phenomenon is common in periods of seasonal change. When spring comes north and south in the fall. In the Southern Hemisphere, south of the Tropic of Capricorn, the radio reception conditions will worsen.
arrive in the northern latitudes good times for fans of distant radio stations. For listeners in Europe is a good time to disappoint stations in Latin America, and for listeners in North America is a good time to tune the Pacific and East Asia. The remote stations are disappointed in the dark part of the day (night), in bands of 90 to 49 meters, on shortwave.
To this end, in addition to a suitable recipient, you also need a good antenna. It should be noted immediately that the antenna inside the enclosure (internal antenna) is not adequate for capturing distant signals at low frequencies. Regardless of how giving notice, this antenna will always experience interference from AC power cables (which in Europe is 220 volts) of the various appliances, highlighting first devices with cathode ray tube (televisions, monitors , etc.).
For this reason, the listener must make an antenna located several meters from each of the buildings where there are such cables and equipment. In this case, the cable that connects the antenna to receiver radio should be protected by a metal sheath (tube, tape or a network). Can be used, for example, a coaxial cable of 50 ohms of resistance, whose metal casing must be properly grounded or connected to the metal tube of cold water, radiator central heating, etc. The antenna itself may consist of a bare wire strung between tall buildings, poles or trees alive.
Wire Binding to these elements is done with strings of isolation, each of which should be not less than two meters long. The conductor of the antenna itself should be separated by no less than two meters from other metallic structures. They exist in near AC conductors, the distance from them should be not less than three meters. In such circumstances it is desirable that the antenna is perpendicular to such drivers. As antennas also capture various interfering signals (noise atmospheric or man) should add filter elements, for example, an antenna within 1.8 x 1.8 square meters, with three turns (turns), and a capacitor AC adjustment.
manufacturers offer multiple antennas made with great features, very expensive indeed. Between antennas that listeners tend to develop on their own, offering the best EWE antenna performance consists of two vertical conductors of 3.5 meters long each, joined by a horizontal bare wire of seven meters. This antenna is directed and is well suited to capture signals in the tropical band shortwave.
listeners may find many other types of antennas using existing compendia, or by checking the information on the Internet. However, the best suggestions will receive the most seasoned DXers who have already assembled and tested antennas and plant.
English version by Raina Petkova
"Area DXers" 03/27/1911
Radio Bulgaria.
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