Key Product Information

​​FCC Design 

ETS-Lindgren has incorporated contemporary materials, precision manufacturing and select improvements (such as Type N connectors for balun and cable connections) to the optimally matched, compensated balun design used by Willmar K. Roberts at the FCC laboratory. The result is a quality product that provides years of use.

Low VSWR and Balun Loss 

The model 3121D has an average VSWR of less than 1.6:1 and a balun loss of less than .5 dB throughout its frequency range of 30 MHz to 1 GHz.Appropriate for EMI Testing and Site Attenuation ETS-Lindgren's Tuned Dipole Antenna is suitable for both commercial and military EMI emissions and immunity testing. The model 3121D also can be used to perform site attenuation per EN55022 and ANSI C63.4.

Quality Construction Complete with Accessories 

ETS-Lindgren's Tuned Dipole is constructed of lightweight corrosion resistant elements, providing years of trouble-free indoor and outdoor service. A clamp block, delrin support rod, and aluminum mounting base are included in the set. The aluminum mounting base accepts standard 1/4 in x 20 threads from an ETS-Lindgren Tripod or most other tripods. All components, including a tape measure, and ruler which shows corresponding frequency, are included in a shock-resistant carrying case.


Specifications Select a tab below for more information

Impedance (Nominal): 50 Ω 
VSWR: <1.6:1 
Pattern Type: Omnidirectional 
Polarization: Linear

​Maximum Continuous Power
​Balun 1
​30 MHz to 60 MHz
​​Type N (f)​
​260 W
​Balun 2
​60 MHz to 140 MHz​
​​Type N (f)​
​Balun 3
​140 MHz to 400 MHz​T
​​Type N (f)​
​80 W
​Balun 4
​400 MHz to​ 1 GHz
​​Type N (f)​
​50 W

  • Two Low-frequency Adjustable Elements
  • Base Drilled to Accept ETS-Lindgren or Other Tripod Mount with Standard 1/4 in x 20 Threads
  • Two Medium Frequency Adjustable Elements
  • One (1) 5 m Tape Measure
  • Support Rod
  • 7.6 m (25 ft) Cable with Type N Connectors
  • One High Frequency Ruler for DB4
  • Four (4) Element Extension Rods
  • Carrying Case
  • Clamp Block
  • Both Stinger and EMCO Mounts Included
  • Actual Individual Calibration Factors and Signed Certificate of Conformance
  • Users Manual
  • 4-TR Tripod
  • 7-TR Tripod


Key Features

  • ​Frequency Range 30 MHz to 1 GHz 
  • FCC Design 
  • Low VSWR and Balun Loss 
  • Individually Calibrated 
  • Appropriate for Site Attenuation Measurements
  • Both Stinger and EMCO Mounts Included

Literature and Videos<a href="/sites/etsauthor/ProductBrochures/General%20Brochures/Test_and_Measurement_Full_Line.pdf"><img alt="" src="/_layouts/15/IMAGES/icpdf.png" />Test_and_Measurement_Full_Line.pdf</a>

L o a d i n g

 Catalog-Item Reuse