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Two-way operation is essential for satisfactory telephone service, and many of the problems of the industry arise from this fac..

Telephone Circuits - Two-way operation is essential for satisfactory telephone service, and many of the problems of the industry arise from this fact. A simplified circuit for obtaining two-way operation is shown in the below figure. This is called a local-battery system because..

Telephone Lines - The transmission lines used in telephony are of two kinds: open- wire and cable. The open-wire lines are gradually being superseded by cable construction, either overhead or underground, for two principal reasons. In the first place, many more circuits can be accommodate..

A microphone is a device that transforms sound pressure into electrical energy. In most types of microphone, the sound pressure acts upon a thin plate or diaphragm, setting it into vibration, and this mechanical motion is then utilised to produce electrical effect..

Microphones - A microphone is a device that transforms sound pressure into electrical energy. In most types of microphone, the sound pressure acts upon a thin plate or diaphragm, setting it into vibration, and this mechanical motion is then utilised to produce electrical effects. The chief types ar..

What fraction of telephones are colored green ? => 1 2 or 1 4 or 3 8 or 3 9..

What fraction of telephones are colored green? => 1 4 or 4 9 or 3 8 or 1 2..

Brad's telephone bill for the month of January was $40 and that for the month of February was $70. What was the total telephone bill for those two months? => $70 or $30 or $110 or $2800..

The installation charge of a telephone is $208, which is 73% of the total expenditure for a new telephone connection. Find the total expenditure. => $284.93 or $285.93 or $287.53 or None of the above..

Tim′s telephone bill for the month of January was $30 and it was $40 for the month of February. What was the total telephone bill for both the months? => $60 or $65 or $70 or $80..