When a subscriber picks up the telephone, the switch hook ______.

The resistance of the telephone loop varies because of the resistance of the __________ element

The local loop resistance depends considerably on the ________ of the twisted pair between the telephone and the central office

•The frequency response of the local loop is approximately ________ Hz.

An unloaded twisted pair has an upper cutoff frequency of about ______ kHz.

When long runs of cable are used, special __________ are inserted into the line to compensate for excessive roll-off at the higher frequencies.

The tip wire is green and is usually connected to _______.

The ring wire is red and is usually connected to the _______

The _______ in most older telephones is an electromechanical bell.

The ___________ is the microphone into which you speak during a telephone call.

In a standard telephone, this microphone uses a _______carbon element

The receiver, or earpiece, is basically a small _______ speaker

The _______ is a transformer-like device that is used to simultaneously transmit and receive on a single pair of wires

A small amount of the voice signal produced by the transmitter that occur in the receiver

All telephones contain some type of component or circuit that provides automatic voice level adjustment so that the signal levels are approximately the same regardless of the loop lengths. This is done using ______.

•A varistor is a nonlinear resistance element whose resistance changes depending upon the amount of ______ passing through it.

The original telephone system designed for full duplex analogue communication of voice signals

The two-wire, twisted- pair connection between the telephone and the central office is referred to as the ______

__________ techniques is now used in PSTN

Another name for COs

First Long Distance Telephone service was in ________

Systems employed by telcos that can connect any two telephones

Each telephone must have a unique identification code known as _______

First manual Switchboard debuts in __________.

The local loop resistance depends considerably on the _______ of the twisted pair.

The frequency response of the local loop is approximately ________ Hz.

The two wires used to connect telephones are labeled _____.

The resulting ac voice signal produced on the telephone line is approximately ______.

The ______ is a transformer-like device that is used to simultaneously transmit and receive on a single pair of wires