ETS-Lindgren (EMCO) 3109 Biconical Antenna

ETS-Lindgren's Model 3109 Biconical Antenna uses a modified Guanella​​ balun for impedance transformation and matching. The Model 3109 provides a broad frequency range and because it is constructed of much heavier materials, it has a maximum continuous input power up to​ 1 kW, with a peak power handling capability up to 2 kW. While this antenna typically has a high VSWR at frequencies below 70 MHz, it is still capable of generating a high field strength with acceptable input power in this region of the band. The optional extended elements markedly improve its performance in this region. This antenna is ideal for IEC 1000-4-3 testing.

The assembly design of the Model 3109 provides for easy storage and portability. The standard biconical elements are made from welded aluminum. The 4-to-1 ratio balun network is fabricated from TFE thermoplastics and specially machined brass and aluminum support and contact parts. The bifilar inductors of the balun are wound in precision machined cuts to provide high barrier insulation between windings while simultaneously giving good coupling between bifilar windings.

The Model 3109 is individually calibrated at 1 m per SAE ARP 958 and 3 m and 10 m per ANSI C63.5. Actual factors and a signed Certificate of Calibration Conformance are included. Because slight variations in testing environments can affect the field characteristics around an antenna, it is recommended that a field probe be used to accurately determine the field strength in the region under test.