EPE Conseil Cemprotec 31 EMF Monitor

Cemprotec 31 RF Meter: Simple, Compact Radio Frequency Detection

The Cemprotec 31 is a handheld radio frequency meter for anyone who wants a quick, clear picture of the wireless signals around them, without reading numbers off a screen. It picks up signals from mobile phone networks, cell towers, WiFi and Bluetooth across a wide 1 MHz to 10 GHz range, and shows the level on a scale of 24 colored LEDs. It is designed and made by EPE Conseil, and it replaced the ESI 21. Browse our full range of EMF meters to compare it with other options.

What the Cemprotec 31 Detects

• Mobile phone networks, including 2G, 3G, 4G and 5G, and cell towers
• WiFi networks
• Bluetooth devices
• DECT cordless home phones
• FM radio and TV broadcast signals
• Radar systems

24 LEDs Show the Signal Level

The Cemprotec 31 uses a scale of 24 colored LEDs, so the more LEDs that light, the stronger the signal. The scale covers power densities from 0 to 2750 µW/m², and the manual includes a table of the numerical value for each LED. An audio function lets you hear the signal as well as see it, which helps you tell sources apart as you move around a room.

Cemprotec 31 Frequency Range and 5G

The Cemprotec 31 detects radio frequency signals from 1 MHz to 10 GHz. That includes the sub-6 GHz bands used by most 5G networks, as well as 4G, WiFi and Bluetooth. It does not reach millimeter wave 5G, which starts at 24 GHz. For that, choose the FM5 Path Complete, which reads 24 to 32 GHz. The Cemprotec 31 shows how strong a signal is, not what frequency it is on.

Easy to Use

The 9V alkaline battery is included, so it is ready to use as soon as it arrives. Switch it on, point it at the area or device you want to check, and watch the LEDs. Readings rise as you move closer to a source and fall as you move away, so you can compare rooms, check a router or a cordless phone, and see whether a reading changes after you move a device.

Compact and Lightweight

The meter measures 7.0 x 2.0 x 1.3 inches and weighs just 4.2 oz, so it is easy to carry in a bag and use anywhere.

Cemprotec 31 vs Cemprotec 32, 33 and 34

EPE Conseil makes four Cemprotec meters, and we sell all of them. The number tells you what the meter measures, not simply how advanced it is:

• Cemprotec 31 (this meter): radio frequency only, from 1 MHz to 10 GHz, shown on a 24-LED scale. The simplest and lowest-priced way to check WiFi, cell tower and Bluetooth signals.
• Cemprotec 32: low-frequency electric and magnetic fields (10 Hz to 5 kHz), plus powerline communication (PLC) and dirty electricity signals (1.6 MHz to 68 MHz). It does not measure radio frequency such as WiFi or cell signals.
• Cemprotec 33: low-frequency electric and magnetic fields (10 Hz to 5 kHz) plus radio frequency (1 MHz to 8 GHz), in one meter. It has 7 LEDs per field type (14 levels), and a Full HF mode with up to 21 levels for radio frequency.
• Cemprotec 34: the same three field types as the 33, but with a wider radio frequency range (1 MHz to 10 GHz) and a finer display: 8 LEDs per field type (15 levels), and a Full HF mode with up to 24 levels for radio frequency.

In short: choose the 31 if radio frequency is all you want to check, the 32 if your concern is wiring and powerline signals, the 33 for radio frequency and low-frequency fields in one meter at a lower price, and the 34 if you want that same coverage with the widest radio frequency range and the most detailed display. See the Specifications tab for a side-by-side table. If you want numerical readings, see the TriField TF2, or the FM5 Path for directional tracing and millimeter wave coverage.

Made in France by EPE Conseil

The Cemprotec 31 is designed and made in France by EPE Conseil, a French manufacturer of electromagnetic field detectors.