Posted by Circuits Arena on Thursday, 11 February 2016
Amplifier Working and How Amplify Weak signal to Stronger signal is the artlcle explaining Amplifier Working General Amplifier is a device which takes in a weak electric signal and sends out a stronger one. Amplifiers are used...
Amplifier Working
General Amplifier is a device which takes in a weak electric signal and
sends out a stronger one. Amplifiers are used to boost electrical
signals in many electronic devices, including radios, televisions, and
telephones. Both vacuum tubes and transistors can be amplifiers, though
today vacuum tubes are rarely used for this purpose.
Weak-signal
amplifiers are used primarily in wireless receivers. They are also
employed in acoustic pickups, audio tape players, and compact disc
players. A weak-signal amplifier is designed to deal with exceedingly
small input signals, in some cases measuring only a few nanovolts (units
of 10-9 volt). Such amplifiers must generate minimal internal noise
while increasing the signal voltage by a large factor. The most
effective device for this application is the field-effect transistor.
The specification that denotes the effectiveness of a weak-signal
amplifier is sensitivity, defined as the number of
micro volts (units of 10-6 volt) of signal input that produce a certain
ratio of signal output to noise output (usually 10 to 1).
