Acoustimeter (AM-10 & AM-11) Radio Frequency Meter
©2024 by the EMF Center, EMFCenter.com
“The Acoustimeter is an excellent meter for measuring the wireless RF fields from cell towers, cell phones, smart meters, computers, Wi-Fi, and most of the 5G frequencies being used at this time.”
(Michael Neuert, EMF Engineer and Health Consultant)
↓ Video Instructions: How to Use the “Acoustimeter AM-10” (Note: The AM-11 is Very Similar to Operate.) ↓
↓ Below is Michael’s 5-Minute “Quick Summary” Video — How to Use the Acoustimeter to Measure RF Fields… ↓
The Acoustimeter is an RF Test Meter That We Have Recommended for Many Years
For many years, the Acoustimeter was our favorite RF test meter to recommend for clients and students – for accurate and sensitive detection of modern digital radio frequency (wireless) fields. When we were selling and renting test meters, it was the main RF meter we offered. (And it was also the minimum level of RF meter that Michael recommended to students who were going to do professional testing of other people’s homes.)
The Acoustimeter AM-11 is the Newest Model of Acoustimeter
The Acoustimeter AM-11 is generally similar to the original AM-10 model. It measures the same range of frequencies, using the same measurements units. But there are several important upgrades to the AM-11. First, specifications released by the manufacturer show that the AM-11 has a better (flatter) frequency response curve. This means that the measurements are generally more accurate than the previous version. (Remember that no RF meter is perfect, they all have certain inaccuracies.) The other two upgrades are that there is now a helpful button on the front to reset the Peak Hold (Max Peak) function, and the volume adjustment is more accessible on the front.
Many Important Features, Including a Numerical Display
The Acoustimeter has many important and helpful features, including a digital display which gives you detailed measurements of the instantaneous peak, peak hold, and average RF levels:
(1) Numerical display of peak, peak hold, and average measurements
(2) Helpful LEDs for quicker assessment of peak and average levels
(3) High sensitivity, accuracy and reliability
(4) Detection of frequencies from 200 MHz up to 8 GHz
(5) An audio function to help you determine sources
Helpful Audio Function
The audio function transforms modulated (pulsed) RF signals into a distinct sound pattern that you can hear. This is very helpful when you are trying to determine sources. Different RF sources have different sound patterns that you can learn to recognize — for example, a cell tower vs a smart meter, vs a Wi-Fi router, vs a DECT phone.
Detection of 5G Frequencies?
At this time, most of the frequencies used for 5G are the same as for 4G, and the Acoustimeter picks them up very well. And in the future, as 5G systems begin to add higher new frequencies above 8 GHz, those 5G systems will continue to emit a substantial amount of the older 4G frequencies — because frequencies under 8Gz are still the best for getting through walls, into buildings, and traveling further distances.
We also Like and Recommend the Safe and Sound “Pro”
Another very good RF test meter — in the same approximate price range as the Acoustimeter — is the Safe and Sound Pro II. This is the RF meter that we generally recommend most often now, for clients and students. Like the Acoustimeter, the Safe and Sound Pro has a numerical display, a helpful audio modulation feature, and it detects the same frequency range from 200 MHz up to 8 GHz. Both are excellent meters, but in my opinion, the main downside of the Acoustimeter is that its numerical display is harder to understand, and that it measures peak and average levels in different units, both of which are a little confusing.
Other Good RF Test Meters — On a Budget
The Acoustimeter and the Safe and Sound Pro both cost around $400 in the US. If that cost is too high, there are 2 good meters available for around $200. One is the Acousticom-2, which is similar to the Acoustimeter but without the digital number display. The other is the Safe and Sound Classic, which is similar to the Safe and Sound Pro, but without the numerical display. All of these RF meters measure the same frequency range, and have the very helpful audio feature.
Special Note About Low Cost Meters
We are generally concerned about the accuracy and reliability of most of the other low-cost (below $200) RF test meters that are on the market. For measuring RF fields, this is especially true for the multi-purpose test meters which try to measure all three kinds of EMFs in one instrument. We have seen a lot of issues with accuracy and quality. If you really need to save costs, the TriField TF2 can be considered, but it does not have the same sensitivity, accuracy or audio modulation feature as the better meters, so generally we would recommend the Acousticom-2, or at least, the Safe and Sound Classic.
Key Features and Specifications of the Acoustimeter AM-11
Key Features and Specifications…
- Name of Meter: Acoustimeter Model AM-11.
- Test Meter Measures: Radio frequency (RF) fields.
- Frequency Range: 200 MHz up to 8.0 GHz (±6 dB).
- Type of Antenna: Single-axis.
- Type of Fields Detected: Both digital (including 5G) and analog RF/microwave fields.
- Audio Feature: Special sound function helps determine and distinguish specific RF sources.
- Measurement Modes: Peak (instantaneous), peak hold (max peak), and average types of RF measurements.
- Units of Measure: Peak: Volts per meter (V/m), Average: microwatts per meter squared (µW/m²).
- Sensitivity: Peak mode ranges from 0.02 V/m to 6.00 V/m, and average mode is from 1 µW/m2 to 100 000 µW/m2.
- OLED Display: Bright numerals showing “Peak”, “Peak Max” (Hold), and “Average”.
- LED Display: Two vertical rows of colored LEDs that show “Peak” levels in V/m, and “Average” levels in µW/m².
- Battery: Uses two AA batteries (included).
- Size: 190 mm x 102mm x 33 mm (LxWxD).
Summary – Both models of the Acoustimeter, the AM-10 and the AM-11, have these important features: (1) an audio function to help you determine sources, (2) detection of frequencies up to 8 GHz, and (3) high sensitivity, accuracy and reliability
Important Feature #1 – Up to 8 GHz: The Acoustimeter measures RF/microwaves from 200 MHz up to 8 GHz. This is important because some RF meters can only detect up to about 3 GHz, completely missing the 5.0+ GHz frequencies of newer cordless phones and Wi-Fi routers. The Acoustimeter detects the RF emissions from most cell towers and cell phones, cordless phones, microwave ovens, Wi-Fi routers, Bluetooth, smart meters, TV channels 12 and up, and most other digital devices in our modern wireless world. And this includes most of the 5G frequencies being used at this time (which are generally below 8 GHz). Please note that the frequency range of this test meter does not include frequencies below 200 MHz, such as AM, FM and some TV broadcasting, and some ham radio frequencies.
Important Feature #2 – Special Audio Function: The Acoustimeter has a special audio feature that can help you determine and distinguish various RF sources. In addition to a speaker with volume control, it has an audio output socket for headphones or to feed to an audio recorder. With a small amount of practice, you can learn to recognize the distinctive reproduced sound patterns from different types of RF sources. For example you can learn to distinguish a cell tower signal, from a Wi-Fi router, from a smart meter, etc.
Important Feature #3 – High Sensitivity to Digital Signals: The Acoustimeter is one of the best RF meters available today for capturing the relatively “difficult to detect” peak pulses from low-level digital RF signals. Thus it can detect relatively weak digital signals that many other meters miss. This makes it an ideal RF meter for highly sensitive individuals.
Important Feature #4 – Peak Hold Function: This is a very helpful function. You can turn on the test meter meter, then sweep around the entire room with the meter, and it will record or “hold” the maximum peak measurement it has received since it was turned on. This maximum peak level is perhaps the most important number to consider when measuring and comparing radio frequency exposures.
Important Information from the Manufacturer:
The Acoustimeter reads differently from some meters as:
- It has a very fast response (up to over 8 GHz and reacts to very short pulses)
- Peak readings are what they say – the highest sampled reading – though the sampling and processing rate means that there are some gaps and it will not always react to a SINGLE VERY short pulse (less than about 5 microseconds duration) – though it will react correctly to much shorter pulses that are regularly transmitted (such as from WiFi). The peak-hold reading on the LCD screen can be higher for some types of signal than the highest LED seen flashing as the Peak LED display does not show all the pulses in order to make it easier to see. The LCD peak-hold is the highest measured since switch-on. It is cleared by switching the meter off and on again.
- The Average reading is a true mathematical time-averaged reading of about the last 1000 samples. This gives the correct reading for DECT and WiFi and is much lower (DECT average power is about 0.01 of the DECT pulse power) than many other instruments which use the highest peak reading and then translate that into an equivalent average power. That is not correct as power is measured as total energy used/delivered per second and not the energy in a short pulse of say 10 milliseconds followed by a 990 ms gap. It is important that we understand this as most international standards are based on true average power (actually usually averaged over 6 minutes!).