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First let me explain how it works, because you need to know how it works.
1. A 20 mVpp( Peak to peak ) goes into the circuit
2. It goes through a capacitor which blocks any DC voltage from traveling from any side of the amplifier, and it also can filter (or "block" out) any unwanted frequencies.
3. The capacitor removes all DC offset and the signal goes into the next stage, a voltage divider.
4. The voltage divider( in this case R1 is the 47kOhm resistor and R2 is the 5kOhm below it ) adds around 1.9V DC, into the signal, adding DC offset.
5. The signal is then travels into the amplifier
Let me explain the parts of the amplifier.
The top resistor ( 5kOhm top right ) is designated Rc ( Resistor Collector ). The bottom right resistor is Re ( Resistor Emitter, 1kOhms ). The Re and Rc resistors are often mentioned as the "biasing resistors". The cap next to Re is to smoothen the amplification, and filter out frequencies. The amplifiers gain is set by using the formula G( Gain ) = Rc/Re = 5000/1000 = 5 , we have a gain of 5. Now, the transistors collector voltage is dictated by a few factors, the gain, the supply voltage, the base current, base voltage, and the signal's frequency. Don't worry if you run into a problem you've never seen before, everything can be solved by undoing things slowly and observing the changes. An example would be when you are oversaturating a transistor, the symptom of this would be bat man coming out of your output instead of an amplified signal.
Lets continue
6. The signal goes into the base and exits through the emitter. The 100uF cap then helps keep a stable voltage at the emitter.
7. Now, the amplified signal is now at the collector. Observe the wave and notice how it has ~13V of DC and 2.75 Vpp AC.
8. Now that amplified signal goes through the output capacitor, a 10uF cap that filters out DC and certain frequencies. The result is a sine wave of 2.75Vpp.
If you need any help understanding, ask in the comments.
Feedback appreciated.
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