A.H. Systems manufactures a wide variety of EMI loop antennas in the frequency range of 20 Hz to 30 MHz. Loop antennas are primarily used to measure the magnetic field strength at lower frequencies. The small size of these loop antennas has the advantage of convenience in handling, availability of a zero- response orientation, and a simple expression for the voltage produced by a given field strength. At higher frequencies, about above 100 MHz, a loop of practical size may no longer be electrically small and has a significant response to the electric field as well as the magnetic field.
Whether used in a set to measure shielding effectiveness per MIL-STD 285 and NSA 65-6 or individually to satisfy specific requirements, the Loop Antenna is an efficient, low cost solution.