GSM repeater Signal GSM-80A A6740 amplifies the signal inside the building. It is an ideal device for use where there is insufficient signal for your mobile phone and is suitable for various buildings and spaces where gsm signal coverage is difficult (underground and reinforced concrete structures, bars, games rooms, etc.) Which are shaded by sheeting or wide walls.

The device is no longer on sale because of its unreliability. We service the device permanently from the competition.

EAR-200 - Quality test equipment for wall and window rustling

EAR-200 - Quality test equipment for wall and window rustling

Battery microphone to check the rustling of walls and windows. By attaching it to a protected wall, the headphones can easily detect the level and efficiency of piezoelectric converters and transducers..

SPY SHOP SLOVAKIA - Wholesale security system

SPYPHONE PRO INTERCEPTOR PLUS - GSM Spyphone

ur GSM Interceptor traps voice calls and SMS so you have the ability to get a number or listen to, record or redirect calls, control both with GSM 900MHz & 1800MHz GSM mobile network. From its description, the hybrid system is active in operation, but does not use any direct connection to the real network, does not use any call forwarding, and critically does not use any illegal system that disables encryption. In short, it uses all the controls of a fully active system with all invisibility passive system.

Hytera PD785G digital radio stations programmed for group encrypted calls ! Digital DMR system. 

Digital radio stations with call encryption for DMR, TETRA and TetraPOL systems. These are European ETSI standards, which guarantees interoperability with radio stations and third-party infrastructure. All radio stations meet demanding army standards MIL810 C / D / E / F, IP67 coverage and of course meet the requirements of RoHS. Extensive accessories are available for all radio stations.

Highly sensitive personal detector VF array 0.5MHz - 20GHz. Multipurpose sensitive high frequency array detector. It allows the immediate value of the signal strength to be targeting, detecting the active eavesdropping device, including determining the distance of the transmitter. Unique is software capable of detecting and subsequently detecting the most technologically inseoter digital and pulse eavesdropping devices.

High frequency field detector.

Multipurpose sensitive vf field detector. It allows the measurement of the instantaffing value of the force of the vf signal, the search of the active transmitter, has the possibility of determining the distance of the transmitter.

Radio bedbug, common parameters in the 94MHz frequency band ---- 98MHz, Range approx. 50m.

Description: Working voltage: 1.2V----- 9V 

Working current: 

3mA@1.2V, 

25mA @ 9V 

Professional portable 80g tracking device designed for convenient tracking of persons, vehicles, or goods over the Internet.

GEOLOC iT200 small, compact electronic device, designed to locate persons, motor vehicles and other mobile objects.

We currently offer the equipment to pensioners at a 5% discount. They can be easily found by relatives via the web portal after entering the correct password. Unless, of course, they forget their GPS device.

Wavecom? The right choice for you?

W61CL OR W-CODE-CL

altClassifier and Code Check (CCC) Classifier and Code Check (CCC)

The WAVECOM classifier is an important analysis tool for classifying unknown signals. Wavecom is an important analysis tool for the classification of unknown signals. The purpose is to determine the modulation type, baud rate, frequency shift and bandwidth of one or more signals. The goal is to determine the type of modulation, the baud rate, the frequency and bandwidth of the shift of one or more signals.

This option is only available for government bodies! This option is only available to government authorities!

GSM amplifier in 3G band

You don't have a GSM signal, but you can capture the GSM signal near you. - Use an active GSM signal amplifier. GSM - REPEATER. GSM 3G signal amplifier, including antennas.

A New Opera Interview Sheds More Light On Wii BrowserThe device is a duplex amplifier in the GSM band 900MHz. It serves as a repeater – gsm signal amplifier, which is transformed from the external environment into an internal environment, so-called shaded spaces, where in normal conditions the GSM signal does not receive sufficient quality. It is suitable for places in buildings where there is no signal (garages, tunnels, cellars, alpine hotels), but at least at some point GSM signal you have sufficient – roof, window upstairs...

The Huawei B2368 is a gesignete, but it's also ready to support future 5G networks!

The modem contains an external drive and an internal modem. It leads to an Ethernet cable with PoE power that ends in the internal unit. The internet spreads using 3x 1Gbit LAN and wirelessly using 802.11a Wi-Fi/b/g/n/ac.

1.3 Megapixel IP mini camera from LAN output and VIDEO IP-697, suitable for camouflaged assembly

• Small size ( 42X42X28mm ), easy installation

• HDTV 1.3MP High Resolution Pinhole Lens

• Use also for low lighting

The TE-9102B GSM signal amplifier is a GSM broadband amplifier suitable for boosting GSM signals even in larger objects. The number of callers is not limited.

The device is no longer on sale because of its unreliability. We also perform service on a given device permanently from the competition.

Network LAN-WiFi Music File Player Cocktail Audio X-30 • CD/USB/Ethernet/WiFi/Internet Player music files of all sorts of formats including 24bit FLAC HD and WAV files

All In One HD Network Player Of Cocktail Audio X-30 Music Files • CD/USB/Ethernet/WiFi/Internet Music Player of all sorts of formats including 24bit FLAC HD and WAV files • Available designs: Black / Silver • Installation hardisk: optional – no hardisk

A modern household with a 100-pro wife who welcomes that he doesn't have to wipe dust from a number of components is the target audience for the Coctail Audio X-30.

In one locker, the manufacturer offers an amplifier, CD player, tuner, internet streamer, archive storage and a lot of user comfort.

GSM amplifier in 900MHz PROFI MAX-AT-800 band

You don't have a GSM signal, but you can get the GSM signal near you. - Use an active GSM signal amplifier. GSM - REPEATER. 900MHz GSM amplifier including antennas.

The device is a duplex amplifier in the GSM band 900MHz. It is suitable for places in buildings where there is no signal (garages, tunnels, cellars, alpine hotels), but at least at some point gsm signal you have sufficient – roof, window on the floor...

For new designs please consider the USRP N210 instead. --- USRP2 Package, includes Motherboard, Enclosure, SD Card, 2 RF Cables, Ethernet Cable, Power Supply, and Hardware Package.

For new designs please consider the USRP N210 instead. --- USRP2 Package, includes Motherboard, Enclosure, SD Card, 2 RF Cables, Ethernet Cable, Power Supply, and Hardware Package.

Transcrypt's SC20-430 offers voice privacy protection in front of almost all but the most determined and technically possible. From rapidly changing codes to an average of 250 times per second, the SC20-430 sends a signal that is inexible to most of each listener. Despite having mixed audio of its own production, it is incomprehensible, the back voice is clear and natural sound.

Compatibility: Offers the ability to install high quality voice security on hundreds of brands and models of two-transmitters.

Very low Power: Limits the effect on the battery life of portable radios.

Voice quality: Provides clear, natural sounding speech and voice recognition, while working superbly in security mode.

Uniden UBC 3300 XLT Trunking Scanner

The Uniden UBC 3300 comes with ten searches for banks that should be sufficient for most of the population's needs. These can be set up with any search range, step size or mode such as AM, FM, or NFM WFM. Alpha also tagging is a feature that can be used with search pots (or as uniden moves to call).

While in search mode up to 200 frequencies can be locked to search ranges. As with the 780 recovery locked frequencies is a simple matter of pressed down the L/O button for 2 seconds. Simple and effective, great!

Also, the military airband will default up to 50 kHz when the international standard is 25 kHz.

Network type GSM 900 , GSM 1800. Dimensions 0.99*0.184*0.44 cm. Weight 74 g. Standby time Hours. Talk time Hours. Display 106*56

General Network type GSM 900 , GSM 1800

Band Dual Band

Control Inputs Directional Pad

Shape Bar/Tablet

Call Manage Call Divert, Call Wait, Caller Id

Dimensions Height 9.9 cm

Depth 1.84 cm

width 4.4 cm

Weight 74 g

Display Display Width 106

Display height 56

Display Type LCD

Display Colors Monochrome

FLEX-6000 ™ Signature Series transmitter is based on new hardware architectures and SmartSDR ™ software platforms. This new ultra-high performance defined radio software uses Digital Down Conversion (DDC) to convert from RF directly to digital broadcast and digital up conversion (DUC) to convert from digital to RF. Flex-6000 utilizes spectral Capture ™ units (SCU) for RF digital conversion and ultra high performance onboard signal processing and control system, to perform demodulation and modulation, filtering and audio stream management. The result is incredible dynamic receiver range, ultra-low phase noise and phenomenal received signal clarity. 

Broadband receiver DJ-X11E Along with a large device that now includes digital output.

50 kHz to 1.3 GHz continuous frequencies, modulation modes from SSB FM and broadband

memory and scans show the requirements of the actuachi

ALINCO DJ-X 11E-hand receiver, NEW 2012

Under the previous top model ALINCO DJ-X200 returns with a new range, trumpeting handheld scanners on the market.

Broadband receiver DJ-X11E Along with a large device that now includes digital output.

50 kHz to 1.3 GHz continuous frequencies, modulation modes from SSB FM and broadband

large memory and scan show the requirements of akteullen appropriate devices

Personal eavesdropping detector and frequency meter iDetektor RAKSO-120

Modern miniature detector and frequency meter

Detection and identification of analog and digital wiretaps

Frequency range: 50 - 3800MHz

Work modes: audio and vibration

Colour OLED display 128 × 64

PC-based digital monitoring system.

Basic features:

X graphics resolution up to 640x480 points.

X optional MPEG4 or Wavelet compression.

X remote monitoring via LAN, WAN or telephone network.

X remote internet access.

X recording based on motion detection or timetable individually for each camera.

X Watch dog ensures reliable operation of the system during the absence of operation.

Uniden USC-230 - an excellent scanner not just for the go

Very fast receiver with frequency range from 25 to 1300MHz. This handheld comfort scanner offers everything an experienced user needs.

Equipment: 2500 channels, delayed search / Delay - 2s, noise canceling control (Squelch), scan function, block keyboard, battery pointer, channel search speed: 100 channels / s, speed of frequency search: possibly 300 (Hyper Search) steps / s .

Technical data:

Frequency ranges: 25.0000 - 54.000 MHz, 108.0000 - 174.000MHz, 216.000 - 225.000MHz, 400.0000 - 512,000 MHz, 806.0000 - 956.0000MHz, 1240,000 - 1300.000MHz

Frequency steps: 5 / 6, 25 / 8,33 / 10/12, 5/15/20/25/50/100kHz,

Number of channels: 2500

Dimensions: (h x in x h) 73 x 139 x 35mm

Weight: 179g.

GSM STAR version "A" Basic model with built-in microphone. It is equipped with 4 inputs, 2 of which are callers and 2 allow sms. After calling from an eligible number, you can eavesdrop on the protected area.   

It is possible to make a special adjustment and insertion of a special microphone brand knowles with a large sound range of 15-25m. You get the cleanest sound from a buged room in HiFi quality !!! Supplement 130,-€

As accessories we recommend Professional Flood Sensor - water sensor

Portable Broadband Receiver AOR AR-mini

Japanese company Authority on Radio (AOR) / 1 / occupies a leading position in the development of broadband receivers and has gained a reputation also in professional monitoring. The new AR-mini continues this tradition.

The AOR receiver includes the full frequency area from 100 kHz to 1299,995 MHz and modulation types: narrow FM, wide FM and AM. The reception options are thus concentrated on FM, on monitoring the operation of manual AM stations from the CB band (11 m) above and on the radio signal in the area of frequency DV, SV, KV and VKV. The desired channel raster (debug step) can be selected from 5 to 100 kHz. The digitisation of thetorical television (DVB-T) in Germany is now almost complete.

GSM GATE version "B" Variant with LCD display that displays the status of the device.

GSM Relay - switch GATE version "B" Variant with LCD display that displays the status of the device. It is equipped with 4 inputs, 2 of which are callers and 2 allow sms. In addition, i have two outputs that can be switched via SMS.

As accessories we recommend professional flood sensor - water sensor.

Basic features:

1. after activating input 1. or 2. calls 2x2 preset phone numbers or sends 2 different SMS (inputs 3 and 4.),

2. remote interception of the monitored space (only from the authorised number stored on the po.5 SIM card, only the version "A"),

3. The device may fully replace the simple control panel

4. connection of any sensor (magnetic, PIR, etc.),

5. The ability to connect as a GSM device to any device,

6. possibility of use in the car,

7. High reliability of the device,

8. no need to use a mobile phone, GSM STAR includes a quality integrated GSM/GPRS module operating at 900/1800MHz frequencies,

9. near-zero operating costs

As accessories we recommend Professional Flood Sensor - Water Sensor

Motorola

Alt

380-430 MHz , mit Farbdisplay und Tastatur.

About 1 Watt Sendeleistung

About TETRA SDS Statusübertragung und

Datenanwendung

About Hochauflösendes Farbdisplay 130x130 Pixel

About Integrierter 1 Watt Lautsprecher

About Vibracall ®

About Gruppenruf + Einzelruf

About Abmessungen HxBxT mm : 125x50x37.5

About Gewicht: 233 g mit Standard 1850mAh Li Ion Akku

About Betriebsdauer 12 Std bei (90/5/5%)

About Schutzart IP54

About Inklusive Standard Software Bends GPS,

About Inklusive LI-ION Akku 1850mAh

About Inklusive Wendelantenne 11 cm

About Inklusive Tischladegerät

PC-based digital monitoring system.

It consists of a digitisation card and software. It goes beyond the capabilities of traditional analog video switches, multiplexers, and advanced video recorders. While maintaining high frame rate, the system allows you to connect up to 16 cameras. It also offers high-quality digital video recording, remote surveillance of cameras, video archive and multi-camera monitoring. For some cameras, the system also supports positioning and zooming from your PC screen. The GeoVision product line includes a wide range of capture cards from 4 to 16 cameras in versions ranging from 16 frames to 400 frames per second.

The wireless invisible micro-handset is a top-notch hi-tech product of the highest quality. It is used for hidden communication. Thanks to the miniature dimensions, it is applied directly to the ear canal and the signal is transmitted to it via a magnetic VF loop, which is applied around the neck under the clothing. The magnetic loop also contains a microphone and is connected to a mobile phone.

This is first the audio signal is converted into a magnetic signal, and then transferred to a conventional profi earpedo.

This system is actually something like invisible handsfree. No one will notice you have it. Ensures maximum comfortable and discreet communication. The sound is clear and loud enough.

NETIO 4 is a network device that allows you to control the power of external devices connected to 230V outputs over a computer network. NETIO 4 includes one input per 230 V and four 230V power sockets that allow you to connect almost any 230V-powered device. The device's web interface is accessed from your local network or the Internet using an Internet browser or mobile phone.

The output switching can be controlled by an internal timer, or the buttons on the front panel can be used for immediate output control. NETIO 4 also allows for easy integration into most systems through Telnet or CGI command – the application can be controlled, for example, by automatic external scripts, etc.

Scanlock Select Plus - Scanlock ECM Plus, lap-top, Cerberus 2RF analysis software

Scanlock Select Plus - Scanlock ECM Plus, lap-top, Cerberus 2RF analysis software

Automatic RF detector signals working in páaltsmu 8 kHz - 4 GHz. Input BNC connector 50 W, max. 13 dBm. Automatically searches for all RF signals and displays the frequency. It has a built-in speaker for the signal. Programming the prelcd display. Sage 610x430x220 mm, weight 6.3 kg. Charging from a built-in battery with a capacity of 8 hours. Output to hearing aids and tape recorder. Under scanlock select plus, it's a deliverable. computer and evaluation SW, which allows you to display the spectra of the spectrum and save the data.

SPY SHOP SLOVAKIA - Wholesale security system

Uniden Bearcat BCD396XT is the latest digital trunking handheld scanner, released in March 2009. The 396XT Scanner is a feature-filled powerhouse that represents huge progress over its predecessor BC396T recently completed. With advanced microprocessors, huge memory capacity and an unparalleled effort to offer features and technologies that scanner fanatics and professional users have long aspired to, Uniden has hit another home run out of the park with a BCD396XT portable. We congratulate Uniden's U.S. product management and their group's Japan-based research and technical team for providing us with a sensational new scanner.

The 396XT handles the APCO-25 digital decoding and automatically does it very well.

GPS OnLine EU-HCT2-432, GPS system from tracking even via GSM cellphone in real time. Watch who you need and do it for free. 

 A unique GPS system that you can mount in seconds. Or you're just going to put it under the back of the car. Easy setup and subsequent real-time tracking even that is possible today. No registration and monthly fees! You only create a GSM card and follow. 

Online GPS monitoring system to your car – how does it work?

Manual and automatic detection mode. Possibility to detect all types of eavesdropping. Check the phone line outside the building.

The TPU-6 phone line scan report can detect any interception device on the telephone line, including resources connected to the capacity line. It checks the line in three basic modes:

automatically the result is for each measurement method + or -

manually performing each type of check separately, where the result of the measured value of the audio mode is by listening directly to the telephone line

The device can detect the following interception devices:

high frequency means

serial attached resources

parallelly connected means

highly resistance-mounted means

NEW VoIP ANALYSIS SOFTWARE FOR THE TALAN

Voice-over Internet Protocol (VoIP) phone systems present a new form of security risk to communications. With new enhancements built into the TALAN software interface, users can now test internet protocol (IP) packet traffic on VoIP phones and systems. VoIP data collected by the TALAN software includes Source and Destination Mac Addresses; header type; statistics - total packets; packet rate; peak rate and run time. Users can also define advanced filtering options. Data can be stored and exported to USB or Flash as data files for further analysis, sharing and reporting.

The radio station is made for easy handling, the rubberized belt on the edge ensures that it does not snooze and sticks well in the hand. It is resistant to shocks and vibrations, high and low temperatures, humidity and design was awarded the first prize at the International Forum.

The radio station has a color several line powerful display with high resolution, (can display text and images), menu keys and alphanumeric keypad (with lockable), 2 microphones, upper rotary knob to facilitate selection for the user, is powered by liion rechargeable battery. Possibility of activating gps service.

The OSCOR green spectrum analyzer sweeps at 24 GHz per second and quickly detects the transmitting electronic tracking devices. OSCOR Green's unique integrated automatic switching antenna system requires no additional antennas or cables. OSCOR Green at 9.6lb / 4.4 kg is portable and easy to use. A high resolution touchscreen of 8.4 inches / 21.3 cm puts "drag" and "move" controls on the fingertips.

Compact, truly pocket-sized, universal test instrument designed to measure any digital, on/off analog signal or keying on frequencies from 30 MHz and 2.8 GHz

Specifications

• Impedance: 50 ohms (Socket BNC), VSWR less than 2:1

• Frequency range: 30 MHz - 2.8 GHz

• Sensitivity: less than 5 mV

• Max. input: 15 dBm

• Resolution: 10 kHz for digital signals, or On/Off Keying & 1 kHz for analog signals

• Time base: less than 1 ppm at room temperature

• Weight: 210 g

• Size: 80 mm x 68 mm x 31 mm deep

• Subject: Pressed anodised aluminium with black finish

• Batteries: internal 4 x AA 600 mAh NiCd pack

• Power supply: 9 VDC 300 mA

The CPM-700 is a broadband receiver designed to detect and locate all major types of electronic surveillance devices including room, phone, body bugs, video transmitters, and tape recorders. 

Broadband receivers such as the CPM-700 provide a very important cost-effective tool for professional sweep teams, government security personnel, and private citizens with important security needs.

The CPM-700 is very effective for rapidly detecting and locating transmitted signals, while being very easy to learn to use. The CPM-700 sweep kit includes a custom Cordura case that contains all items necessary to conduct a professional sweep.

Nice little diktafon in a pocket with which you can make a few visions. The dictaphone does not contain displey, but it is still very easy to operate. Nice nice gift.

A miniature dictaphone with its size of 75.5 x 28 x 13 mm can be carried in your pocket or handbag. Miniature dimensions and very nice design, two gigabytes of internal memory (37 hours of audio recording) with the possibility of extending up to eight gigabytes will be very enjoyable. You can use the device as a dictaphone, whether camera, or camera + as an mp3 player, or USB key. All these features create a complete picture of this modern MFP, which will certainly please the user.

When protecting sensitive information is critical to your success, the OSCOR provides the most reliable and cost effective capability in the industry, including detection of sophisticated transmitters (frequency-hopping, burst/packet, and spread spectrum). OSCOR is a complete eavesdropping detection package that is portable and programmable. 

OSCOR is a microprocessor controlled countersurveillance system with a custom designed built-in spectrum analyzer that can operate automatically storing all encountered signals and spectrum traces in memory for later review and comparison. Designed to detect all major types of audio and video RF transmitters (even frequency-hopping, burst/packet, and spread spectrum), including carrier current and infrared.

ORION (The Great Hunter) provides the capability to detect hidden electronic devices, regardless of whether the device is radiating, hard wired, or even turned on at all! ORION is the latest advancement in Non-linear Junction Detection and evaluation for Countersurveillance.

NJE-4000 Advantages

Minimum Set-up Time, no cables or bulky transceiver units to carry

Light weight, balanced ergonomic design for ease of use

High Transmit power for rapidly searching a large area

Circularly Polarized Antenna reduces search time and improves reliability

Dual Harmonic with Discrimination Algorithms Minimizes False Alarms

Standard type camcorder battery with long use time and quick charge function

•One-touch switching between classified and unclassified PDA functions

•First ever on-the-move wireless access to the SIPRNET

•Intuitive, user-friendly interface

•NSA-certified, DISA approved

•In use and available today

EMSER® EDGE™ SMARTPHONE

SECURE MOBILE ENVIRONMENT PORTABLE ELECTRONIC DEVICE (SME PED)

One-touch switching between classified and unclassified PDA functions

First ever on-the-move wireless access to the SIPRNET

Intuitive, user-friendly interface

NSA-certified, DISA approved

In use and available today

Easy, fast deployment with Configuration Tool — lets you update up to 16 SME PEDs at once

PROBE DETECTS SPY UNIT CPM-700 ADVANCED

The CPM-700 U.S. brand REI is a professional high-speed receiver capable of detecting and localizing virtually all types of electronic devices to monitor and radio listening, eavesdropping phone lines, wireless cameras and microwave devices. It also allows measurement of magnetic and acoustic spectrum leakage, which provides a very wide range of possibilities in the field of risk analysis, detection and elimination. Professional effective equipment designed for officer professionals, law enforcement and security for companies that require the highest level of protection against surveillance. It provides rapid and efficient detection and localization of signals on potentially hazardous electromagnetic fields.

SPECTRAL ANALYSER 24GHZ OSCOR GREEN OGR-24

OSCOR Green 24GHz is a professional device for complex electromagnetic spectrum analysis. The version, designed specifically for export, does not require special permission. The equipment is intended for commercial use by security professionals in companies that require special oversight and supervision protection. 

Allows:

Detection and analysis of all unwanted signals, listening

Wireless expansion studies

Radio emission analysis

monitoring of unauthorised use of radio spectrum

SPECTRAL ANALYZER OSCOR GREEN 8GHZ OGR-8

OSCOR Green 8GHz is a professional device for complex electromagnetic spectrum analysis. The version, designed specifically for export, does not require special permission. The equipment is intended for commercial use by security professionals in companies that require special oversight and supervision protection. 

Allows:

Detection and analysis of all unwanted signals, listening

Wireless expansion studies

Radio emission analysis

monitoring of unauthorised use of radio spectrum

DIGITAL RADIO FREQUENCIES DETECTOR AND CAMERA SWEEPMASTER F2560

Sweepmaster F2560 is a fully integrated mobile surveillance protection device, the purpose of which is to detect and determine the presence of hidden spy devices electronically during a search of a vehicle or property. The detector was developed using the latest digital technology, providing very high sensitivity in a wide range of frequencies that can detect even very weak signals that can be transmitted by any device and spyware. 

F2560 allows you to find all transmitters VHF, UHF and microwave bands working in 1MHz -6GHz, such as miniature bugs, cocks installed in the grid, tapping phones, tiny wireless cameras, GPS locator devices, mobile phones, radios, etc.

Sweepmaster F2800 Plus is the latest in integrated threat detection systems, electronic security. There has been increased sensitivity, frequency meter range and new optimized for more options than previously available in detecting and localizing eavesdropping devices and other electronic threats in the house or in the car. 

Thanks to modern digital technology, it was acquired for very high sensitivity in a wide frequency band , and this gives the confidence to detect and locate even the weakest radio signals at 0.1 MHz - 8GHz . Gearboxes are detected by LF, HF, VHF, UHF, microwave and infrared, which can be used by transmitters listening, video transmitters and telephone dialling or two-way radios and devices to track geographic location.

Two-channel noise generator to protect rooms against eavesdropping from outdoor areas. For each channel, the power and intensity of deep and high frequencies can be adjusted separately. Frequency range is 125 Hz - 4 kHz, minimum impedance 2? for each channel. Dimensions 203x140x41 mm, weight 0.5 kg. Power supply 12V DC, 1A.

The ANG-2200 is designed to create a perimeter of noise around a target area that defeats wired microphones inside walls, contact microphones, audio transmitters located in AC outlets, and laser/microwave reflections from windows.