SPICE-Simulation using LTspice IV

The npn transistor BC557B is not included in the LT’s library, so you need the internet again. When youhave
found the model file, copy it into an editor’s new file (do you remember? You receive a HTML file) and save it in
the library folder.
Note: When you have found the model files the transistors are named QBC547B and QBC557B. Use these
names in the spice directive and in the schematic.
The input voltage is a sine wave with a peak value of 100mV and a frequency of 1kHz. Simulation time is 0….10
Milliseconds.
Something new is the command
„.op“
With this command you get information about the DC-values in the circuit (= „DC operating point“). The
information is presented in form of a list.
The test points in the schematic are the voltage source V1 and the termination resistor R9 (75) at the output.
9.2.3. Time Domain Simulation
As required the output voltage’s peak value is twice that of the input voltage and that gives a gain of 6 dB……
Two common emitter stages produce a phase shift of 2 x 180 = 360 degrees. So the output voltage is again in
phase with the input voltage.
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