1. Analysis without purpose is pointless
This set of notes analyzes a common-emitter amplifier circuit in two different ways: Tourbook table and by direct small-signal circuit theory.
It is so important that y’all get physical color prints of them.
2. EF amplifier analysis
Sony radio small-signal analysis.
Figure 1. Sony XDR-F1D sim
Original circuit: Sony_XDR-F1D_audio-amp.pdf
The service manual indicates that the DC voltage at the base of Q103 is about 5.6 V, with the emitter at 5.0 V.
Figure 1 can be treated as two cascaded amplifiers:
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Draw the Q103 amplifier’s small-signal equivalent circuit.
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Find the input impedance Zin.
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Find the open-circuit voltage gain (no load attached to the output) Av0.
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Find the output impedance Zout.