Telephone Systems Quiz

The origin of the word "telephone" comes from two Greek words: "tele" meaning "from afar" and "phone" meaning "sound, voice, or voice sound."

Alexander Graham Bell, assisted by Thomas Watson, was able to transmit words over the telephone on March 10, 1876. Bell was later granted the patent for his invention, number 174,465.

The rotary dial telephone, also known as the Bell System 500-type, was introduced by Western Electric Company in 1951.

AT&T, also known as Bell Telephone System and Ma Bell, provided phone services. They were known for using rotary phones (500-type) and later, DTMF phones (2500-type).

The Main Distribution Frame (MDF) is the point where the telephone network's inside plant (the central office) connects to the outside plant (the network of cables).

A manhole is an underground enclosure that allows access to the splicing of multiple cables. It provides a safe and convenient way to repair, maintain, and connect cables.

A Cross-Connect Cabinet or Serving Area Interface (SAI) distributes cables to different areas of subscribers. These cabinets help manage the flow of signals to various locations near subscribers, and they're typically mounted on poles or fixtures.

A termination box contains the subscriber's telephone line and is the point where the local loop connects to the distribution plant central office. It houses the connections necessary for a subscriber's service.

A connector is the physical interface between the telephone and the telephone line. It allows the subscriber to connect their phone to the network. The connector is typically a standard RJ-11 jack.

A Feeder cable in a local loop is the largest cable, typically carrying a large number of copper wires (up to 3600 pairs). It is responsible for delivering the signals to the other smaller cables in the network.

The part of a telephone that converts sound waves into electrical signals, enabling voice transmission.

The part of a telephone that converts electrical signals back into sound waves, allowing you to hear the voice on the other end.

A device on a telephone used to generate pulses or tones to establish a connection with a specific number.

A component within a telephone that transforms electrical signals from the central office into an audible alert, signifying an incoming call.

A part of a telephone set that provides a path for electrical current to flow when the phone is off the hook, enabling a connection.

A circuit that ensures a clear and consistent voice level regardless of the incoming signal strength.

The sound of your own voice heard through the telephone receiver, providing feedback on your speaking volume.

A device that combines and separates two-wire and four-wire signals, typically used for connecting a telephone to the central office.

A communication method using a series of on-hook and off-hook states to create pulses, transmitting digits over a telephone line.

A dialing method using specific combinations of two frequencies (high and low) to represent each digit, making transmission faster and more reliable.

The state when the telephone handset is placed in its cradle. The line is connected to the ringer, allowing incoming calls to be heard.

The state when the telephone handset is lifted from its cradle. The line switches from the ringer circuit to a talking circuit, enabling communication.

The total amount of signal loss a line experiences, including cable loss, central office loss, and junction loss.

A device used to compensate for signal loss in long telephone lines by reducing the effects of capacitance build-up.

A specific type of cable with a defined loss per kilometer. Different cable types have different signal attenuation properties.

The process of determining the appropriate cable type based on the distance between the subscriber and the central office and the required signal strength.

The resistance of a copper wire loop per kilometer, calculated using the wire's diameter.

The diameter of a wire, usually measured in millimeters, determining the resistance it offers to electrical current.

The wires or cables entering a building, connecting the building's internal wiring to the nearest telephone facility.

The minimum recommended diameter of the conduit used for service entrance wiring, ensuring sufficient space for cables.

The maximum recommended distance from a telephone pole to a building for aerial service entrance, preventing excessive cable slack.

Minimum clearance requirements for telephone cables near power sources and pedestrians, ensuring safety and preventing accidents.

Use PVC or corrosion-resistant materials for underground conduits carrying telephone cables, protecting them from damage and rust.

The minimum recommended depth for burying underground entrance conduits, ensuring protection from damage and interference.

The separation between loading coils is determined by the type of coil used. For example, an 'H' type coil has a separation of 6000 feet (1.8 km).

A common type of loading coil with an inductance of 88 millihenries (mH) added every 6000 feet.

The formula to calculate the number of loading coils needed: N = 1 + (D - 5000) / S, where N is the number of loading coils, D is the distance, and S is the coil spacing.

Unused sections of cable connected in parallel to a working cable pair. They allow multiple subscribers to share the same local loop.

The resistance of a wire pair used for voice transmission. It depends on the wire gauge (size).

The Direct Current (DC) resistance of a wire pair, calculated using the formula: Rdc = 0.1095 / d^2 (ohms per mile), where d is the wire diameter in inches.

Smaller wire gauge results in a larger diameter, lower resistance, and less signal attenuation.