GUIDE TO PHONE TAPS

Guide to Phone Taps

Phone Tap : What is it?

Phone taps are systems used for monitoring telephone conversations by a third party. They were termed as such because they drew off a small amount of the electrical signal from the telephone wire carrying the conversation.

Phone tapping is done as a covert operation. Legal matters such as invasion of privacy have to be considered when using phone taps. Legalized phone tapping (or wire tapping) by the police and other recognized government authority is known as lawful interception. Phone taps are also used by companies to monitor employee performance especially in call center operations.

The law imposes some limitations on how and how frequent tapping can be done. These limitations vary from state to state and from country to country.

Types of Phone Taps

Kinds of Phone Taps include the following:

RF transmitters

RF (radio frequency) transmitters come in small RF transmitter units.
They are attached to the phone line or within the telephone instrument.
The series RF taps, also called leaches, are powered by the telephone line, and therefore do not need frequent battery replacements.
They last long, enabling indefinite operation.
Their listening posts (LP) are receivers that do not require wire lines. They can be located anywhere within the range of transmission, making it more convenient and covert.
They are easy to install.
One RF series in particular, the drop-in, can be installed in seconds. It is placed at the back of the carbon microphone found inside most telephone handsets. The standard carbon microphone is simply replaced with the modified tapped version.

Infinity transmitters

Infinity transmitters are installed in the target area. They operate independently from the telephone.
They use the telephone line by calling from a remote telephone and activating it with a tone signal.
They require their own telephone line.
They work by transmitting the room audio out.
They are not connected to any telephone line within the target area. They can be hidden in any location and connected to an additional phone line.
They can function on Electronic Switching Systems (ESS), without requiring to work around them.
They are sold as common electronic devices for house monitors.
They require equipment capable of activation and detection using remote devices.

Slave parallel wiretaps

Slave parallel wiretaps are one of the most popular professional devices used by the law enforcement community and professional eavesdroppers.
They work like infinity transmitters combined with the features of parallel wiretaps.
The target telephone line and the leased standard working telephone line are connected to the slave.
The eavesdropper calls the lease line to activate the slave.
Upon activation, the eavesdropper's telephone line automatically connects to the target telephone line.

Inductive wiretaps

Inductive wiretaps bring coil windings within the electromagnetic field created by the current fluctuations in a telephone conversation.
The current fluctuations are then induced into the coil windings.
They are further amplified to recover the target conversations.
They are not very effective by themselves, but they can produce satisfactory audio recovery when used with split/resplit inductive wiretaps.
The split/resplit inductive wiretaps rewire the target telephone line to induce the audio conversation into the eavesdropper's line.
They use the inductive properties of the wire pairs within the same cable.
They are commonly used by professional eavesdroppers as they are the safest to use.
They are difficult to detect or located by the telephone company. They can only be detected by time domain reflectometers (TDRs), which are used to spot wire irregularities.

Choosing Phone Taps (Buying tips)

Size and range: Use a small phone tap (usually the size of a pencil eraser) with a broad range of five miles for covert operations. For less setting up activities, look for a pre-concealed transmitter.

Modulation: Choose a phone tap that with an amplitude modulation and a frequency modulation, allowing you to modulate basic operating frequency for better listening quality. You can also get one with more sophisticated modulation features such as pulse amplitude modulation, pulse width modulation, and pulse position modulation.

Anti-detection: Look for a phone tap with burst transmission, spread spectrum, frequency hopping, and snuggling features to make its signals virtually undetectable.

Legal considerations

Phone tapping is strictly controlled to protect an individual's privacy in most developed countries.

In the United States, federal agencies can engage in phone taps only when authorized by the United States Foreign Intelligence Surveillance Court.

In companies and businesses, they usually announce at the beginning of the call that the conversation is being recorded to inform all the parties concerned about the recording.
In some countries like India, phone tapping for business purposes has to be approved by a designated authority; otherwise it is illegal.

Are you Picky, too? Contribute to this guide!

Do you have something to add to this guide? If your suggestion passes our editorial standards, we will add it in and acknowledge you as a contributor.