InnovAntennas DXC-140 40 Meter Rotatable Dipole covers the entire 40 meter band with particularly good efficiency and impressive SWR bandwidth with a very reasonable wingspan, just over 39 feet (12m).

InnovAntennas DXC-140 Compact 40 Meter Rotatable Dipole

There are several methods to shorten a mast-mounted rotatable dipole, including loading coils and capacity hats. The position of the coils is critical to efficiency - closer to center is mechanically easier, further out is electrically better. The designer has used both methods to build the DXC-140 antenna robustly and efficiently, limiting the size to a turning radius under 20 ft. (6 m) that many radio amateurs can easily mount on their tower mast and rotate within their property limits.

The advantage of this design is a very large usable bandwidth of the antenna - the DXC-140 can be used over the entire internationally approved range from 7.0 to 7.3 MHz without having to use a tuner (SWR 2:1 or better). In the DXing range from 7.0 to 7.2 MHz, the SWR is usually equal to or better than 1.6:1, making the efficiency of the antenna 89%!

Due to the robust construction of the DXC-140, no guy wires are necessary. Some of the images of this model installed show examples with guy wires, as chosen by individual user dependent upon the location, due to the expectation of snow and ice, for example. However, the mechanical design and construction will handle heavy loads, with the element diameter of 2.17 in. (55mm) in the center with a wall thickness of 0.078 in. (2mm). The element diameter decreases towards the end of the element save weight, but the ends still have a diameter of 0.98 in. (25mm) to easily support the capacity hats.

All in all, the DXC-140 40 Meter antenna combines a carefully calculated design with a very robust construction from an experienced antenna designer. This is also supported by the materials used: UV-resistant insulators, seawater-proof stainless steel hardware and aircraft grade aluminum elements. The result is a rotatable dipole with high efficiency, with an overall length of only 39.4 ft. (12m) and a weight of only 18.7 lbs. (8.5 kg).