ETS-Lindgren's Model 3102 Conical Log Spiral is made with spiral windings of semi-rigid coaxial cable attached to the outside of a fiberglass cone. The outside windings improve heat dissipation. This cone is attached to a delrin rod equipped with an aluminum base.
Once used exclusively for MIL-STD and SAE testing, conical log spiral antennas are effective for other types of measurements too. For example they can be used for close-in "quick-looks" to find the spectral characteristics of RF emissions. For immunity testing, conical log spirals generate reasonable field strengths with modest power input. By placing conical log spiral antennas in a vertical position with respect to the ground plane, they can also be used as omnidirectional, horizontally polarized antennas for electromagnetic site surveys. The Model 3102 Conical Log Spiral is also used as a communication antenna in support of over-the-air wireless device testing.
The antenna mount base accepts standard 1/4 in x 20 threads from a tripod.