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Short Vertical Phased Array layout. Array is 870 feet wide, 70 feet long, facing a bearing of 65 degrees. Element 4 (composed of 2 antennas in an end-fire array) is fairly close to the transmit antenna (about 200 feet). The diagram does not show the 14 Beverage antennas that cross the array. The layout was chosen as a compromise between size and bearing, the ideal bearing being about 45 degrees, and the ideal size being about 1080 feet (for narrowest main lobe). Block diagram of major components. Note that the direction reversing This is a view of the entire array, so far, from the southeast end, looking northwest. The first set of vertical is 290 feet away, the second set is 580 feet away, and the third set is 870 feet away. The right hand vertical of the second set is nearly impossible to see in this picture (even in the large version). The right hand vertical of the third set is missing, because it broke in two. A-frames of 2x2s are not strong enough. This is a typical vertical. You can almost see the guy wires which double as a top hat. It is made of three 12-foot 2x4s mounted on an 8-foot 2x4 buried in the ground. The overall height is 23 feet. The top hat wires are also 23 feet long, sloping at a 45-degree angle. The combination of wire is resonant around 3.5 MHz. With a 30 uH inductor, the resonance becomes about 1.83 MHz. A series 68-ohm resistor and 16 25 foot radials brings the feed point impedance to 75 ohms. The box in the foreground contains a relay and phasing line that switches the favored direction from northeast to southwest. Power for the relay is decoupled from the feed line. At the base of each vertical is a box (that is supposed to be sealed) that contains the 30 uH loading coil and 68 ohm ?impedance matching? (bandwidth making) resistor. There are 16 25-foot radial wires. 16 radials seem to be sufficient to make the ground impedance fairly constant despite the weather. Vertical #8 in the foreground, and the transmitting vertical in the background. Notice how treated wood cannot support its own weight. This is a relay box and phasing line up close. The array has three of these, so far. From each of these boxes runs a 1000 foot piece of RG6 back to the shack. Having a separate feed line to the shack makes arraying experiments convenient. The inside of one of the direction reversing boxes. The big black box is a relay, and there is a 2:1 transformer to match to the feedline, and a 1;1 transformer to invert the phase of the western vertical. The capacitor bypasses RF around the relay coil. The 1:1 transformer also decouples DC from the RF. Schematic of the phased array end-fire element phasing and direction reversing box. There are 4 of these in the array. This is the equipment necessary for a beam steering receiving system. The system consists of the computer below the table, keyboard and monitor, the laptop to control the DDS-60 local oscillator, and the 4 Softrock v6 receivers in the metal box. The service monitor is for testing. This is the southern half of the array. A long, not terribly effective, NE Beverage crosses the view. A closer view of the 4 Softrock v6 receivers and the DDS-60 oscillator. The red clip lead supplies DC to activate the reversing relays to which the array from east to west.

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