Electromagnetic Meter

Model EM2


Heliognosis developed the first inexpensive omni-directional broadband monitor for measuring all sources of electromagnetic radiation up to microwaves named the emm. This compact device enabled users concerned about potential health risks to locate areas of exposure. Following the success of the emm initiative, Heliognosis has now released the EM2. The EM2 has several improvements over the original emm including improved accuracy, frequency response and ruggedness. The new design includes a fast response analog display for detecting pulsed transmissions from digital equipment such as wifi, cell networks and smart meters. The included rubber boot is comfortable to hold and elegant while providing protection from bumps and falls. The display employs a unique logarithmic scale to capture both very weak and very strong signals without the need to switch ranges. The color coded scale helps to identify safe from dangerous conditions. EM2 bridges the gap between cheap limited response monitors and full spectrum units. No bigger than a mobile phone, EM2 detects all electromagnetic emitters from ELF (extremely low frequencies) up to microwaves. This includes virtually all sources of electromagnetic radiation like:

  • WIFI, cell and mobile phones
  • microwave ovens
  • high-efficiency fluorescent tubes
  • Bluetooth
  • Zigbee enabled home automation
  • radio and television broadcast towers
  • amateur and CB radio
  • laptops and tablet computers
  • Smart meters
  • Wireless routers and access points
  • AC power lines, wall plugs
  • military, aircraft and police band radio
  • Dirty electricity
  • Cell towers and Microwave backhaul
  • Bugs and hidden transmitters


  • Frequency response: 50Hz to 18Ghz
  • Sensitivity range: 0.005µW/cm2 to 40mW/cm2
  • Accuracy: +/- 10% 50Hz to 10Ghz
  • Operating temperature: -10C to +40C, 14F to 100F
  • Battery life: 9V Duracell, approx 50 hours

Using the EM2

Use the Heliognosis EM2 to identify hotspots in your local environment. It is ideal for determining safer distances from electromagnetic sources and locating hidden transmitters. For more information Heliognosis Experimental Report 6: Detecting Electromagnetic Radiation and Minimizing its Health Risks investigates common and less well known sources of emissions.

Our small, sensitive circuit detects the electric field component of the electromagnetic wave and converts it into a visually diplayed signal. Operation is simple - extend the antenna and power on the unit. After activating the power switch, the EM2 will begin displaying the measured electromagnetic field strength. Hold the unit in front of you while approaching potential sources of electromagnetic radiation.The readings will increase as you get closer to the source. Metal objects and buildings will block the radiation. You can use this property to help locate powerful sources located at a distance. If you pass in front of a building and the readings drop, it is likely that the source is behind the building. Driving with the meter on the dashboard or suspended from the rear view meter is an excellent way to survey sources in your neighborhood.

Understanding the readings

The meter scale has been color-coded to simplify the readings. Blue and green signify low levels of EM where as orange and red are high and potentially dangerous. Newer digital electronic devices such as cell phones, bluetooth, internet routers and smart meters all produce pulsed radiation that can be very strong at times, especially close up. These pulses appear as rapid meter movements and there peak strength can be seen by how far up they reach on the scale.