The Narda Broadband Field Meter NBM-520 is part of the NBM-500 family of test instruments. It measures non-ionizing radiation with utmost accuracy and incorporates all the major basic measurement modes.

In contrast with the larger NBM-550, a memory for measurement results has been deliberately left out of the NBM-520. The result is unbeatably easy operation using just 4 buttons, so referring to the operating manual is all but unnecessary. Suitable measuring probes for electric and magnetic field strengths are available for the frequency range from about 100 kHz up to 60 GHz. Socalled shaped probes which have frequency responses that weight the results according to specific human safety standards are available in addition to flat probes with flat frequency responses.

All probes are calibrated independently from the measuring instrument. They include a non-volatile memory containing the probe parameters and calibration data, so they can be used with any instrument in the NBM-500 family.