Operation of the Van Veen Loop in a shielded chamber

The Van Veen Loop or Large Loop Antenna (LLA) has been shown to be invaluable for the rapid characterization of the magnetic fields of certain compact devices such as ballasts for fluorescent lighting. Here, operation of the LLA in a shielded, semi-anechoic chamber is considered, including the calibration/verification of the loop using the folded-dipole verification source described in the standard CISPR 16-2-3. The LLA is characterized experimentally in a typical 3-m semi-anechoic chamber using the folded-dipole validation source specified in the CISPR 16-2-3 standard. It is shown that the response of the LLA is slightly affected by the presence of the chamber, but nevertheless provides accurate measurement of magnetic dipole moment over a very broad frequency range. Specifically, the LLA described here meets the accuracy requirements of the CISPR 162-3 standard over the frequency range of 9 kHz to 30 MHz when operating inside a shielded semi-anechoic chamber of dimensions 9 m (length) x 6 m (width) × 5.4 m (height). It can be concluded that the LLA can be used effectively in a typical shielded semi-anechoic chamber.