The Trifield Meter is a gaussmeter, electric field meter and radio field strength meter in a single unit. When measuring electromagnetic fields (EMFs). the primary concern is usually magnetic fields, which can be tricky to measure. If a less sophisticated 1-axis gaussmeter is used, a reading of zero could result even where the field is strong. A 1-axis meter must be oriented correctly to measure the field (which is a vector). The 3-axis Trifield Meter solves that problem by measuring the true strength of the field regardless of which way it is oriented. Therefore, the Trifield Meter can be scanned rapidly across an area without having to stop at each point to search for the orientation that gives a maximum reading. Another section of the meter detects AC electric fields, which can exist independently of AC magnetic field. The third section detects radio/microwave, such as from a leaky microwave oven. Analog (needle-type) display has very fast response time compared to digital. This meter is good for measuring AC (artificial) magnetic fields rapidly, AC electric fields rapidly, such as from overhead power lines or improperly grounded equipment. Can locate wiring in walls (using the 100XE version) and major RF/microwave sources such as leakage from microwave ovens, or the field near cell towers. Operates about 40 hours on replaceable standard 9V battery, has a low battery indicator.