Updated Aug. 2022
( .pdf version )
So you want to block out listening devices. You are probably here because you feel your privacy has been invaded. Welcome, you are not alone. Many people feel this way. With the proliferation of inexpensive and easily obtainable eavesdropping devices, privacy is harder to achieve now than ever before in history.
In this article, we will just focus on audio eavesdropping devices. If you are more concerned about video surveillance devices we have an informative article and a course that can help you detect spycams yourself. We will discuss how to block out listening devices a bit later, just after how to find eavesdropping devices. The right to privacy is written into the constitutions of over 150 countries. It has a definition in law as well. Simply put, one’s personal matters should not be publicized or disclosed. In 1890 jurist Louis Brandeis mentioned it in a legal paper as “the right to be let alone.”
The types of listening devices we will cover here are audio surveillance devices, commonly called bugs. These are the most common listening device bugs:
- Anything that transmits audio wirelessly at radio frequencies. Examples include FM, digital, Bluetooth, or Wi-Fi wireless microphones, and of course cell phones.
- Anything that records sound for later listening. Examples include a variety of tape, digital, or cloud storage recorders, and of course cell phones.
- Any other thing with a microphone that moves what it hears to some other location. Examples include smart devices (or smart assistants), and other Internet of Things gadgets.
Let’s start by answering some of the common questions people have about listening devices.
Is it illegal to use a listening device?
Electronic eavesdropping without a court order in the United States is generally considered to be illegal. Some of the exceptions to the rule include:
- If you are a party to a conversation being recorded in a one-party consent state. (Thirty-eight (38) states and the District of Columbia.)
- In some states the concept of covertly listening exemption is referred to as, “in the ordinary course of business,” or the “extension phone exemption.” This covers common carriers who need to monitor transmission quality, employee monitoring “for quality assurance,” and legitimate investigative purposes. The concept has also been expanded beyond actual business situations. A parent eavesdropping on their child is one example.
- The inter-spousal wiretapping immunity exemption is based on the theory that spouses can’t testify against each other. This is an old and iffy concept. In recent years, many courts have determined this exemption is no longer acceptable.
By the way, if you are thinking of taking advantage of an exemption, don’t. Laws change and courts interpret rules of law on a case-by-case basis. This article is not to be taken as legal advice. Consult your attorney first if you think you have a good reason to use an electronic listening device or other means of technical surveillance.
Do smart devices listen to your conversations?
Sure, it is what makes them smart. It is why you may want to block out a listening device like this entirely.
The questions you should really be asking (and what you really need to know) is:
- When do they listen?
- Where does your voice go when they listen?
- What is done with what they hear?
- How long is your voice retained?
- What access do company employees, strangers, or law enforcement have?
There is no simple answer. Each type of listening device will come with a different set of answers.
News reports about smart device security failures are plentiful. A few years ago it was discovered that Amazon’s Alexa was sending audio of a private conversation to one of the victim’s contacts. Now, all three major voice assistants are facing a lawsuit for spying.
Tip #1:
Assume all smart devices have microphones and they are continually listening. Assume their controlling software is not perfect, makes mistakes, and is vulnerable to hacking. You will need to unplug smart devices when you want greater assurance of privacy. In short, assume they are listening devices.
How do you stop smart devices from spying on you?
Smart devices are listening devices. In theory, they should only activate when they hear their name being called. The reality is there is no way of telling if they are behaving properly. Just try saying, “a city,” “hey Jerry,” “hey, seriously,” “that’s scary” near an Apple HomePod.
Tip #2:
If you don’t feel comfortable having a listening device in your home, don’t have a smart device in your home.That being said, they are very useful, so controlling them is the next best solution. During times you want privacy from these eavesdropping minions you will need to activate their microphone mute button. If your device doesn’t have a mute button, you will just have to unplug it.
How can I tell if my neighbor has a listening device?
Your first clue will likely be them tipping their hand. Remember the taunt, “I know something you don’t know,” from being a kid. Obtaining confidential information can instill a feeling of power and superiority, but this only works if others know you have it. Thus, amateur eavesdroppers rarely keep their mouths shut. Pay attention and figure out how to block out their listening devices.
Tip #3:
When a neighbor mentions things they shouldn’t have knowledge of, trust your instincts, be suspicious. Read our article Eavesdropping Snoops – The Average Person’s Guide to Stopping Them. It contains time-tested advice which can solve your concerns without having to spend a penny.
Can listening devices be detected?
Generally speaking, they can be detected. While there are a few esoteric exceptions to the types of listening devices the average person is likely to encounter, all are detectable. It is just a matter of combining a few detection techniques, with some knowledge of what types of devices might be used to eavesdrop on you.
Start with what made you suspicious in the first place. It was probably someone who knew something they should not have known. Just a coincidence? Check.
One easy test is to make pretend phone calls from various rooms in your house. Say something interesting that would cause your eavesdropping suspect to say or do something in reaction to hearing it.
If their reaction is quick they may be listening- in real-time -using a radio transmitter or hidden cell phone. Delayed reactions may indicate a hidden voice recorder which has to be retrieved and reviewed periodically. Either way, you have narrowed your search to a particular room or area, and you have an idea of what type of listening device you might find. Now that you know how testing can help you, think up additional tests to cover other situations.
Conduct your tests several times. Once you have elicited three or more positive reactions you will know for certain it is audio eavesdropping and not just coincidence.
Next step… You need to identify the types of bugging devices amateur eavesdroppers use. These searches on Amazon and eBay are instant education.
Tip #4:
Instead of blocking out a listening device, finding it should be your first choice. Once you do that you can remove it, or if you want to leave it in place knowing where it is makes blocking it easier. Once blocked the eavesdropper may return to fix it and you can catch them using your hidden camera.
Avoid buying bug detection gadgets. They often give false positive readings, and they are not made to find all types of listening devices, such as voice recorders. Worse, you may be left with a false sense of security if nothing is found. Grab a good flashlight instead. Conduct a physical search of the area you suspect is being bugged. Be methodical. Closely examine everything you can. Listening device bugs can be well hidden and disguised, but they are not invisible.
Of course, if you are not qualified to take an item apart, like an electrical outlet, don’t. Get someone who is qualified to help you.
If you only want to block out the listening device instead of removing it, you have several options…
- Place something nearby which will sound louder to the listening device bug than room conversations. A radio or fan is an easy fix. A better fix for walls that are shared with neighbors, and sound migration to other rooms, are acoustical noise generators.
- To block a listening device that uses a battery, replace the batteries with dead batteries.
- To block a listening device that is mains powered, unplug it.
- One other solution you may see being sold is the ultrasonic microphone jammer. Read Do Ultrasonic Microphone Jammers Work? before you purchase one.
There is no 100% when discussing security and privacy. It is the age-old question of, “How high do we build the wall, great leader?” The answer is, “Just high enough to keep them out!”
What you have learned here will help you build your wall. Our advice will help you detect and deter amateur eavesdroppers. If your concerns involve corporate espionage please contact us directly for professional assistance.
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Murray Associates is an independent security consulting firm, providing eavesdropping detection and counterespionage services to business, government and at-risk individuals.
Headquartered in the New York metropolitan area, a Murray Associates team can assist you quickly, anywhere in the United States, and internationally.
FAQs
How do I block a listening device? ›
- Open the Settings app on your phone. Then, scroll down and tap Account Services.
- Tap Search, Assistant & Voice. Then, tap Google Assistant.
- Tap on Assistant. Then, scroll down to Assistant devices and tap Phone.
- Tap the Google Assistant slider to turn it off.
Use Several Listening Device Detectors
A radiofrequency detector can scan for transmitters. Turn off all wireless devices, including smartphones and routers, then slowly and carefully move the bug detector around your home. Anything that's broadcasting a radio signal will be found.
Audio jammers are small, usually mobile, devices designed to interfere with the way listening devices operate. When you switch on an audio jammer it masks the sound of a conversation, ruining recordings and impeding live audio surveillance. The way these do this is by emitting white noise.
How far away can a listening device work? ›How Far Away Can Listening Devices Hear a Conversation? Some of these devices can allow someone to hear a conversation from 100 yards away, while others have a range of 300 yards, depending on what type of listening device is being used.
Is there an app to find hidden listening devices? ›Android users have the app Detectify.
It's another app that uses your smartphone's built-in magnetometer to find potential spy bugs. The interface is simple, and easy-to-use. You just scan an area with your smartphone.
Sometimes called "two-party" consent laws, it needs all parties to give verbal consent before recording can occur. As long as one-party consents, the federal Wiretap Act and most state laws that allow secret recordings permit covert recordings. Here are some examples of consent: Directly when one party records another.
How can you tell if a room is bugged? ›Another simple yet often effective method of telling if your house is bugged is to turn off any wired or wireless electronics you know of in the room. And then, stand still and listen carefully for any out-of-place noises that a remote device may be emitting.
How long does a listening bug last? ›Battery life
These devices have come a long way in recent years and many can now offer long life listening with anywhere from 7 days to six weeks standby time. With the right device and a degree of planning, you can listen in for as long as you need to.
Experts advise that the most common spots to hide surveillance devices are spaces where people spend most of their time. In hotel rooms and houses, the target spots include the area near the bed, bathroom, living room.
How do you block laser eavesdropping? ›Visible laser light can be blocked by anything that also blocks conventional light, such as a solid curtain, a wall, or even a sheet of paper. If you do see flashes when all external light paths are blocked, consult your doctor or do an internet search. There can be medical conditions that cause flashes.
Can you jam a recording device? ›
By using multiple high-frequency transducers in an ultrasonic jammer, the jamming devices are able to distort microphone recording devices in the range up to ten meters.
What frequency do listening devices use? ›GSM bugs are micro listening devices that are used for room surveillance, eavesdropping at a long range, and covert bugging of areas. These bugs use the UHF frequency at 433 MHz and 418 MHz.
Can listening devices hear through walls? ›The iPhone feature that has grabbed attention is 'Live Listen'. This feature practically makes your iPhone a spying device as it can let you hear conversations through the walls. The distinct feature came to the surface after a TikTok user, Dalilamouhib, discovered it and posted a video about it.
Where are listening devices placed? ›Lighting fixtures, sockets, cable boxes, and the like are all favorite spots for listening devices. Communications ports, Wi-Fi routers, coaxial connections, and even your VOIP trunk can be vulnerable to listening devices.
Does a listening device need power? ›“Hard-wired” Listening Devices can be imbedded into any electronic device including of course household appliances such as televisions, radios, smoke alarms, plug sockets etc. and take power directly from that device.
How do I find hidden spy devices? ›- Look for Odd Objects. It's a good practice to thoroughly scan your surroundings whenever you enter a new room. ...
- Use a Flashlight. ...
- Use Your Smartphone Camera. ...
- Scan the Wi-Fi Network. ...
- Use a Phone Call to Detect Interference. ...
- Use a Hidden Camera Detector App. ...
- Use a Specialized RF Detector.
Many listening devices operate on or just outside of the FM band. You can check for bugs in your house by turning a handheld FM radio to any and all “quiet” frequencies, then walking around the house. If you hear a high pitched squeal, it is an indicator of a microphone installed somewhere.
Where can I find hidden microphones? ›Look for decorations on the edges of the room that are angled awkwardly to face into the room. Hidden microphones will work best when they're in the center of a room, so they can hear everything equally. Look for decorations positioned on a table in the middle of your room to find hidden microphones.
How do you distort a listening device? ›Quick take: How to block listening devices: Use a noise blocker or white noise generator to block long-distance recording or hidden devices in your home. Use frequency scanners or infrared smartphone apps to find hidden cameras. Common sense is your greatest defense against spies.
What to do if someone is secretly recording you? ›If someone records you without your permission in a way that breaks federal or state law, you can contact a legal professional, sue them, and get them to pay damages. However, a civil lawsuit isn't the worst thing that can happen to those who illegally record people.
Can someone record you without you knowing? ›
California. California requires the consent of all parties, with a minimum consent being the notification that the parties are being recorded in a confidential conversation with an audible beep at particular intervals throughout the recording. Without permission, an individual can face imprisonment and fines.
Who can sweep my house for listening devices? ›You need a professionally trained TSCM debugging technician to sweep your entire home to ensure there are no illegal recording devices, hidden cameras or microphones located in your apartment.
How can you tell if someone is spying on your room? ›Look for discoloration on ceilings and walls.
It may be very small, but a circular spot, no larger than a coin, is a signal that you are being spied on. In particular, small devices such as pinhole microphones or video cameras, rest on the other side of a ceiling or wall and may leave an impression.
- Unfamiliar Applications. ...
- Your Device is 'Rooted' or 'Jailbroken' ...
- The Battery Is Draining Fast. ...
- Your Phone Is Getting Very Hot. ...
- Unusually High Data Usage. ...
- Strange Activity In Standby Mode. ...
- Issues With Shutting Down the Phone. ...
- Odd SMS Messages.
By just listening to existing Wi-Fi signals, someone will be able to see through the wall and detect whether there's activity or where there's a human, even without knowing the location of the devices. They can essentially do a monitoring surveillance of many locations. That's very dangerous.”
Can a mirror stop a laser? ›The best way to stop a laser is to use a mirror to send it away or put some object in the way. The object will absorb the light from the laser much like your clothes absorb some of the light from around you.
How do you block surveillance? ›Also, you can close the curtain or shade on the window to block security cameras. The privacy fence, bamboo curtains and yard shade sails are also effective tools to disable CCTV security cameras. Additionally, you may put up cheap posts with cloth flags along the property line to block the CCTV security camera' view.
What interferes with recording devices? ›Any obstacles on the way of ultrasound reduces its effectiveness against recording considerably. It cannot be hidden behind objects or clothes such as pockets. 2. The device has to be located BETWEEN the speaking person and the recording device.
What is an audio scrambler? ›These devices come in an assortment of styles and functionalities, from RF and digital audio jammers to white noise makers, but each of them works with the same intended purpose: to scramble or obscure recordings, making unwanted surveillance difficult or impossible for someone who is trying to infringe on your privacy ...
Is there such thing as a camera jammer? ›A deauther will overwhelm a WiFi system, forcing the WiFi camera to stop recording if you stand close enough. The accessory only costs about $10-$50. A jammer on the other hand will cost anywhere between $150 to $1,000.
What is a listening bug? ›
A covert listening device, more commonly known as a bug or a wire, is usually a combination of a miniature radio transmitter with a microphone. The use of bugs, called bugging, or wiretapping is a common technique in surveillance, espionage and police investigations.
What is a passive listening device? ›The first passive remote listening device (a microphone that works with no active electronic components) was "The Thing", which comprised a metal cylinder with a thin membrane on one end and a long metal rod extending from the side.
What are the most common listening devices? ›- GSM Bugs. ...
- Miniature Voice Recorders. ...
- Mobile Phones as Bugs. ...
- Radio Frequency (RF) Transmitters. ...
- Phone Taps and Phone Bugs. ...
- Optical Devices.
Under ideal conditions, the range of the male human voice is about 180 metres while still being intelligible. Sound pressure level normally halves (by six decibels) for each doubling of distance, so you might still be able to hear the speaker's voice at 360 metres even if you can't understand what they are saying.
How do you hear what someone is saying through a wall? ›To hear through walls, start by finding a drinking glass with a wide rim. Then, hold the rim of the glass against the wall you want to listen through and rest your ear on the bottom of it. Sound waves will travel through the wall and into the glass, making it easier for you to hear through it!
What is Bluetooth eavesdropping? ›Eavesdropping allows a malicious user to listen to or intercept data intended for another device. Bluetooth uses a frequency-hopping spread spectrum to prevent this attack.
How do spy listening devices work? ›How Do Listening Devices Work? Hidden audio recording devices work with special microphones that record and pick up sounds, which can be transferred to a computer into high-quality format audio files. Most of our products are voice-activated, weight-regulated, durability-tested, and equipped with high-quality tech.
What is the smallest listening device? ›THE WORLD'S SMALLEST MICRO VOICE RECORDER
This small recording device measures at . 7in x 1.8in x . 24in. But aside from the fact that it truly is tiny, it is featured packed and simple to use.
Simply download a hidden camera detector app and scan the area for any devices. The app will create an alert if any are found. Using a flashlight to check for unusual reflections in objects is another easy way to find a hidden camera; the lens will reflect the light back, drawing attention to the hidden device.
Can you use a laser as a listening device? ›A laser listener is a surveillance device that uses a laser beam to detect sound vibrations in a distant object. A laser listener is designed to allow eavesdropping with a minimal chance of exposure.
How can I tell if my house is bugged? ›
And don't forget that using a hidden camera detector or an RF signal detector is the best way to know for sure whether your home, office, place of business, or vehicle has been bugged with hidden microphones, cameras, phone line wiretaps, or any other type of illegal surreptitious surveillance devices.
How do you check if your room has a hidden camera? ›- Look for Odd Objects. It's a good practice to thoroughly scan your surroundings whenever you enter a new room. ...
- Use a Flashlight. ...
- Use Your Smartphone Camera. ...
- Scan the Wi-Fi Network. ...
- Use a Phone Call to Detect Interference. ...
- Use a Hidden Camera Detector App. ...
- Use a Specialized RF Detector.
- Unusual sounds during calls. ...
- Decreased battery capacity. ...
- Phone shows activity when not in use. ...
- Phone takes a long time to shut down. ...
- Battery temperature feels warm. ...
- Receiving unusual texts. ...
- Increased data usage. ...
- Android.
Experts advise that the most common spots to hide surveillance devices are spaces where people spend most of their time. In hotel rooms and houses, the target spots include the area near the bed, bathroom, living room.
How do I find a hidden microphone? ›Sweep the area with an RF detector.
RF detectors allow you to scan for radio frequencies used to transmit from hidden cameras and microphones. Purchase an RF detector online or from your local electronics store and wave it around the area you think is bugged.
A wall microphone is used to hear through walls, any kind of sounds, by the sensors in direct contact with walls or ceilings up to 70 cm thickness . A contact microphone is composed of a microphone capsule, a diaphragm transducing sound vibrations into audio signals, a voice processor and a pre amplifier.