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Can an amplifier have negative gain?
Negative gain means the output is inverted from the input. For the gain to be negative, the output would have to go down when the input goes up, which is clearly not happening in your case.
How does a transistor affect voltage?
A small AC voltage at the transistor base generates a small base-emitter current which is amplified by the transistor to give a larger AC collector current. This amplified collector current through the collector resistor creates an AC voltage that is greater than the input voltage, thus the input voltage is amplified.
Is attenuation negative gain?
A negative gain equates to an attenuation… e.g. -20 dB gain is same as 20 dB attenuation… In conventional cables, attenuation is usually specified in terms of the number of decibels per foot. The less the attenuation per unit distance.
Is transistor a current amplifier?
Transistors are normally used as amplifiers. Some transistor circuits are current amplifiers, with a small load resistance, other circuits are designed for voltage amplification and have a high load resistance and others amplify power.
How does a transistor work as an amplifier?
The load resistance is of high value which causes a large voltage drop. Overall, the weak signal is thus amplified in the collector circuit. However, to work as an amplifier, the transistor has to work in the active region of the output voltage versus input voltage curve as seen in the figure below.
Why does a transistor have a low resistance?
The low resistance in input circuit, lets any small change in input signal to result in an appreciable change in the output. The emitter current caused by the input signal contributes the collector current, which when flows through the load resistor R L, results in a large voltage drop across it.
Why is the impedance in a transistor amplifier high?
In the transistor amplifier the input impedance should be high because it will stop the loading of the circuit. For example if the we give 10V signal with 1k ohm source impedance to the 1M input ohm which is connected to the input of the transistor or other electronic peripheral then the input impedance will be
How is the input and output of a transistor connected?
In the figure given above, the input is connected in forward-biased and the output is connected in reverse-biased. The input signal is applied on the base-emitter junction and the output is taken through the load in emitter-collector junction. There is also an application of DC voltage in the input circuit for amplification.