Operation of a Conventional Telephone
• The ordinary home telephone receives the electrical power that it needs for
operation from the local exchange via two copper wires is called (Plain old
telephone service) POTS
• This subscriber line, which carries speech signals as well, is a twisted pair
called a local loop. The principle of the power supply coming from the
exchange site makes basic telephone service independent of the local
electric power network.
• Local exchanges have a large-capacity battery that keeps the exchange and
subscriber sets operational for a few hours if the supply of electricity is cut
off. This is essential because the operation of the telephone network is
especially important in emergency situations when the electric power
supply may be down.
Microphone
• When we raise the hook of a telephone, the on/off hook switch is closed
and current starts flowing on the subscriber loop through the microphone
that is connected to the subscriber loop.
• The microphone converts acoustic energy to electrical energy.
• The ordinary home telephone receives the electrical power that it needs for
operation from the local exchange via two copper wires is called (Plain old
telephone service) POTS
• This subscriber line, which carries speech signals as well, is a twisted pair
called a local loop. The principle of the power supply coming from the
exchange site makes basic telephone service independent of the local
electric power network.
• Local exchanges have a large-capacity battery that keeps the exchange and
subscriber sets operational for a few hours if the supply of electricity is cut
off. This is essential because the operation of the telephone network is
especially important in emergency situations when the electric power
supply may be down.
Microphone
• When we raise the hook of a telephone, the on/off hook switch is closed
and current starts flowing on the subscriber loop through the microphone
that is connected to the subscriber loop.
• The microphone converts acoustic energy to electrical energy.
