Heavy usage of 49 MHz, 88-108, 143, 171, 470, 900-925 MHz bands. Wireless Microphones, Intercom Systems, Baby Monitors, Tape Recorders, Recorder Starter Relays, Inexpensive Microphones, Video Cameras, Camcorders
Restricted Professional Products
The products are typically not sold retail, but are offered into very specialised vertical markets such as the broadcast or recording industry. The most popular products are UHF and VHF wireless microphones and industrial wireless video systems.
These products include those used by Private Investigators, Security People, and related professional with heavy concentration on video based products and are readily available to via mail order, the Internet, or retail channels (such as spy shops). Equipment used for taping phone lines will normally contain a sophisticated isolation circuit, and will be very difficult to detect electronically. Such a device is often called a "Slave Device" and is typically only found via a careful physical inspection.
Examples:
Body Wires, Bumper Beepers, Tracking Devices and Beacons, Wireless Microphones, Tape Recorders, Covert Video Cameras, Night Vision
Professional Products
These products are strictly taboo for the public to buy, sell, possess, or attempt to possess. This level of threat involves eavesdropping products strictly available only to law enforcement agencies, and then only when acting under an ACTIVE court order. Most of the products operate on bands allocated for law enforcement activities, or bands specifically allocated for.
This type of device is usually monitored by full time staff at a fixed command post. The eavesdroppers will typically have the target under intense physical surveillance and will be monitoring "guard-bands". This type of threat is that commonly used when businessmen "bug" each other, and when "big dollars" are involved.
Examples:
Wireless Microphones, Digital VLF Devices, Covert Video Cameras, LAN/WAN Eavesdropping Devices, Bugged Copy Machines, Bugged Fax Machines, Bugged Computers and Monitors, Modified Telephone, PBX, and Voice Mail Systems, Cellular Interception Systems, Beeper/Pager Intercept Systems
Signals Intelligence Products
Frequencies typically between 3 kHz and 110 GHz Wide/Narrow band spread spectrum, burst and frequency hopping Infrared devices between 300nm to 1710nm Those products are used by the Signals Intelligence community, and may include radar analysis systems and communications intercept systems.
This equipment is typically used only by major defence or intelligence agencies and generally is not available to law enforcement. The equipment may include special classified or unclassified battlefield communications systems, SATCOM systems, GPS systems, Avionics Systems, and so on.
Intelligence Agency Eavesdropping Threats
Frequencies typically between 3 kHz and 110 GHz
Wide/Narrow band spread spectrum, burst and frequency hopping
Infrared devices between 300nm to 1710nm
An example of this level of threat is the eavesdropping devices and methods actively being used by an intelligence agency.
This includes both radiated, and conducted signals threats along with various types of intercept systems, alarm bypass systems, covert entry devices, and so on. Virtually all equipment involved in this level of threat is classified at least Secret.
National Security Eavesdropping Threats
This is the highest level of threat which is available to government agencies, and includes emerging technologies, and equipment or devices on the cutting edge of science.
Access to even the slightest piece of information regarding this type of system is highly restricted and requires a high level security clearance. Often people (even with a Top Secret security clearance) are only allowed to work on a small part of the system to minimise the risk of any one person crippling national defence.
The equipment, methods, and activities are all centred around large scale national surveillance, reconnaissance, eavesdropping, and intelligence programs and related activities. A prime example of this is the US National Reconnaissance Office and their program or overhead imagery, or the US National Security Agency/Navy undersea fiber optic tapping ships, or ECHELON.
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