Those meters will measure High-frequency EMF radiation.
Cell towers, smart meters, Wi-Fi (e.g. routers and modems), Bluetooth devices (e.g. printers, headsets, wireless keyboards), cellular & cordless phones, remote controls (e.g. for your garage or car), microwave ovens, and any other device which transmits wirelessly.
Recommended meter for beginners: Tri-Axis meter HF-B3G meter
Recommended meter for advances users: Tri-Axis meter HF-B8G meter
This meter is applied to measuring electromagnetic fields of 2.45 GHZ (microwave frequency) or normal (50MHZ~3.5 GHZ). It is capable of measuring the electromagnetic field radiation intensity that is produced from welding equipment, microwave oven and other environment causes Microwave oven leakage detection
HFE35C is an ultra-broad frequency range RF meter and EMR advanced detector, allows an easy monitoring of the personal exposure to HF/RF electromagnetic radiation in frequency range from 27MHz to 3.3 GHz.
The radar module sets standards in this category of devices. Its functions and features are tailored to the needs and practical experiences of the building biology. Due to its comparably low price, it is often also used for scientific and industrial purposes, especially in the cell phone and wireless sector.
In addition to the full functionality of the HF58B:
A switch for 2 MHz video bandwidth, allowing especially precise measurements, also of ultra short RADAR signals within the frequency range subject to measurement with a minimum pulse length of up to 0.5 micro seconds, as well as of UMTS-FDD/3G.
Especially high speed of response in the operational mode "peak hold" (patented).