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In a manual exchange the caller cranks a magneto which generates 120VAC across the tip/ring pair, on the operator's switchboard this voltage energises a solenoid that releases a flap next to the caller's jack. The caller then picks up the handset, the hookswitch on the phone then connects in a dry cell battery to power the mouthpiece/earpiece and the tip/ring pair. The operator then plugs into the caller's jack and resets the flap, then asks "Number please?". The power from the dry cell battery in the caller's phone is used to transmit the voice signal from the operator's mouthpiece to the caller's earpiece, the caller answers the operator and the power from the dry cell battery in the caller's phone is used to transmit the voice signal from the caller's mouthpiece to the operator's earpiece. The operator then plugs into the jack for the person being called and cranks a magneto which generates 120VAC across the tip/ring pair for that line, this causes the bell on the phone to ring. When the called phone is answered, the hookswitch on the phone then connects in a dry cell battery to power the mouthpiece/earpiece and the tip/ring pair. The operator then flips a switch that connects the two lines and the customers can talk, with their dry cell batteries powering the call.
In an automatic exchange a lead acid battery supplies 48VDC across the tip/ring pair (this will power the phone), the caller picks up the handset, the hookswitch on the phone then connects in the mouthpiece/earpiece and a dialing mechanism to the tip/ring pair. This current draw by the phone is detected in the exchange and triggers the process of beginning a call. An AC dialtone signal is sent to the phone to tell the caller the system is ready to accept a number. When the caller begins dialing (either rotary pulse or touchtone) the AC dialtone signal is removed and the digits dialed are recorded in a register. Once the number being called is captured and looked up, the exchange connects a pulsed 120VAC 5Hz ring signal across the tip/ring pair for that line, this causes the bell on the phone to ring. When the called phone is answered, the hookswitch on the phone then connects in the mouthpiece/earpiece and a dialing mechanism to the tip/ring pair. This current draw by the phone is detected in the exchange and triggers the process of connecting the call through, the customers can talk with power from the exchange's lead acid battery that supplies 48VDC powering the call for both phones.
What else can I help you with?
Do telephones work without electricity?
NO!
Do telephones use a small amount of electricity?
If your telephone came with a charger then yes it uses a small amount of electricity. This is what the charger does, it replenishes the electricity that the telephone used while not connected to the charger.
How have telephones and electricity help shape the modern world?
Well did they shape a circle or triangle
How can the Gosselins be broke?
they have like a million kids.. who all eat.. and use electricity, and computers, and telephones etc.. PLUS they're going through a divorce, which is expensive anyways.
Which invention do you consider important the telephone or electricity?
For me, well, telephones wouldn't work without electricity :|
What is some technology that the France use?
Care to ask that in slightly better english? France use: Cars Electricity Vibrators Trains Telephones Computers Nuclear Power Stations The frog easy de-legger
Inventions that became popular from the year 1850 to 2000?
Trains, televisions, automobiles, airplanes, telephones, electricity,
What is a carbon grain?
something you use for telephones
Did you ever noticed that when the electricity goes out but the phone often sill works Why?
Traditional telephones are powered by the local telephone exchange and do not need to be connected to a mains supply. Modern telephones often use a separate supply to power the additional features of telephones such as memory diallers, number displays, wireless handsets and so on. Most better designed modern telephones will allow the phone to be used as a basic telephone even when local power is lost. Cordless phones will not work when the home power is lost.
Does Mexico use telephones in 1930?
Yes. Telephone companies had made their way into the region by 1905 as a matter of fact. So indeed there were telephones in use during the year 1930.
What does the telephone help with?
We use telephones to talk with. These days, people use cellphones .
Which religious group in Pennsylvania still relies on horses and buggies for transportation and refuses to avail themselves of both electricity and telephones?
The Quakers
