== Running a Network Analysis of the BJT Amplifier ==
[[File:RF116new.png|thumb|640px|The RF BJT Amplifier with S-parameter RF BJT model for AC network analysis.]]
At this point, your BJT amplifier circuit is ready for an overall Network Analysis Test. Replace Q1 (the standard BFG193 model) with NP1 (RF BJT model of BFG193). Place the "IN" marker right after the source resistor, and place the "OUT" marker at the load resistor. Replace the AC voltage source with a piece of wire as shown in the opposite figure. Run a network analysis of this circuit with start and stop frequencies set at 500MHz and 1500MHz and with a linear frequency step size of 10MHz. Plot the S-[[parameters]] on an amplitude-only Cartesian graph. The figure below shows the results for s11, s21, s12 and s22 [[parameters]].