Topband: BOG Antenna?
kc8qvo at yahoo.com
Thu Nov 9 15:35:25 EST 2006
Gary, I studied a similar setup a while ago. Only, I was going to go for the wire above ground and the zig-zags in a vertical plane. The wire was to be 500 feet long and be attached to a rope about 100 some feet long.
The issue with this kind of antenna (the BOG and terminated, as well as unterminated beverages) is that the antenna works on the principal of the wave passing lengthwise over the wire to induce current along the wire. That current is what passes through the transmittion line into the radio. The longer the wire the stronger the current (to a point), and thus the stonger the recieved signal (using a preamp is a must though as the signal is quite weak). When you take that strait length of wire and bent it the radio waves can no longer travel along the length of the wire. Radio waves travel in a strait line, so any curve or zig-zag in the antenna wire will render it useless. The point of the BOG and Beverage antennas is to be directive, high gain recieving antennas. Once you bend the wire to any significant degree the antenna looses its directivity and sensitivity.
What I did instead in my situation was build a K9AY switching loop system. It will recieve in 4 different directions, or, rather, will null out 4 different directions (the lobes are rather broad, not incredibly directive). The recieve performence is NOT going to be what you would get out of Beverages, but it will be better than all but the best transmitting antennas (if you are running a 4 square or 9 circle you need no RX antenna HIHI, a full size vertical or dipole WAYYYY up probably would work just fine on RX too, the vertical might be a little noisy though).
Also remember, there is no harm in trying something new! Thats what this hobby is all about. Experiment, learn, and have fun doing it!
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