Procedure

• Gain.vi is the main VI that obtains the voltage gain as a function of collector bias current. Open Gain.vi and verify that VBB(init) is set to your value for IC=0.1 mA and VBB/Vs=5. VCC(init) will be forced to 1 V in the execution of Gain.vi. Keep subVI GainSub.vi open to help observe the measurement in progress and to obtain Front Panel information for the maximum current. Verify that the correct data are defaulted in the Front Panel of GainSub.vi. The resistors values are not reset in the top VI.
  
  
• Open 5COLDATA.vi. Open VIs using Browse>>Show VI Hierarchy from the main VI.

  

  
  
  
• Run Gain.vi to obtain the gain for a range of collector current with maximum I_C ≈ 1mA. Note that there is a 500 ms delay between bias steps to allow the capacitor to charge to steady state. Verify that Chan1_out(Max) (bias plus signal) does not exceed 10 V. Set the file mode switch to Get File. Run the VI to obtain a data file.
  
  
• The data file includes results for I_C, a_vb, β_DC, and β_ac and r_π. The data provide for making a comparison between measured data and SPICE computations in the Mathcad project file. Default and save the Front Panel of 5COLDATA.vi for a data file backup. Default the Front Panel of Gain.vi to save the value of VBB for the maximum current. Default and save the Front Panel of GainSub.vi to save the value of VBE at the maximum current.
  
  
• For obtaining a file from the saved data in Gain.vi, use GainData.vi. Transfer the data from the three Indicator Graphs of Gain.vi to the three equivalent Control Graphs in GainData.vi. Run GainData.vi to obtain the data file.