This is a common-emitter amplifier, which amplifies the input voltage by about 10 times. The capacitor and the 110 kΩ and 10 kΩ resistors bias the transistor's base at about 1.7 V, so that the average of the input is raised to this level. The base-emitter junction acts as a diode, so the emitter will be a diode drop below the base. Since the transistor stays in the forward active mode, the collector current will be 100 times the base current. The emitter voltage swings with the input voltage, so the current through the 1 kΩ resistor swings proportionally. Since the collector resistor has the same current but its resistance is 10 times greater, the collector voltage swings 10 times more (and with a phase opposite to the input). Note that the peak value at the output is not 5 V, as this analysis predicts. The actual gain, for various reasons, is about 9.5 times. For example, the base-emitter drop is not constant but depends on the base current.
This page is a utility for simulating усилитель с общим эмиттером online with specified initial values.
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